U.S. patent application number 14/748444 was filed with the patent office on 2017-06-01 for method of making a metal primer insert by injection molding.
The applicant listed for this patent is True Velocity, Inc.. Invention is credited to Lonnie Burrow.
Application Number | 20170153098 14/748444 |
Document ID | / |
Family ID | 55016776 |
Filed Date | 2017-06-01 |
United States Patent
Application |
20170153098 |
Kind Code |
A9 |
Burrow; Lonnie |
June 1, 2017 |
METHOD OF MAKING A METAL PRIMER INSERT BY INJECTION MOLDING
Abstract
The present invention provides a method of making a
substantially cylindrical insert by metal injection molding by
providing a primer insert injection mold to form a substantially
cylindrical metal primer insert, injection molding the metal
injection molding feedstock into the primer insert injection mold
to form a first substantially cylindrical metal primer insert
having a first size; debinding the first substantially cylindrical
metal primer insert to remove the first binding agent; and
sintering the first substantially cylindrical metal primer insert
to remove the second binding agent and form the substantially
cylindrical metal primer insert having a second size.
Inventors: |
Burrow; Lonnie; (Carrollton,
TX) |
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Applicant: |
Name |
City |
State |
Country |
Type |
True Velocity, Inc. |
Dallas |
TX |
US |
|
|
Prior
Publication: |
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Document Identifier |
Publication Date |
|
US 20160003593 A1 |
January 7, 2016 |
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Family ID: |
55016776 |
Appl. No.: |
14/748444 |
Filed: |
June 24, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14011202 |
Aug 27, 2013 |
9546849 |
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14748444 |
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13292843 |
Nov 9, 2011 |
8561543 |
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14011202 |
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61456664 |
Nov 10, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B22F 5/06 20130101; C22C
33/0285 20130101; B22F 3/10 20130101; B22F 3/225 20130101; B22F
5/00 20130101; C22C 1/0458 20130101; C22C 38/18 20130101; C04B
35/64 20130101; F42B 33/02 20130101; F42B 5/30 20130101; F42B 5/307
20130101; B22F 3/004 20130101; F42B 5/02 20130101; F42B 33/001
20130101; F42C 19/0807 20130101; C22C 14/00 20130101; C22C 33/0257
20130101; C22C 38/48 20130101; C22C 38/58 20130101; F42B 5/025
20130101; C22C 38/42 20130101; F42C 19/083 20130101; C22C 38/44
20130101; B22F 2998/10 20130101; C22C 38/04 20130101; C22C 38/02
20130101; F42B 33/00 20130101; B22F 2998/10 20130101; B22F 1/0077
20130101; B22F 9/04 20130101; B22F 3/225 20130101; B22F 3/1021
20130101; B22F 3/1025 20130101 |
International
Class: |
F42B 33/00 20060101
F42B033/00; B22F 3/00 20060101 B22F003/00; B22F 5/00 20060101
B22F005/00; C22C 38/18 20060101 C22C038/18; C22C 38/04 20060101
C22C038/04; C22C 38/02 20060101 C22C038/02; C22C 14/00 20060101
C22C014/00; C22C 1/04 20060101 C22C001/04; C22C 33/02 20060101
C22C033/02; C22C 38/58 20060101 C22C038/58; C22C 38/44 20060101
C22C038/44; C22C 38/42 20060101 C22C038/42; C22C 38/48 20060101
C22C038/48; C04B 35/64 20060101 C04B035/64; B22F 3/10 20060101
B22F003/10 |
Claims
1. A method of making a substantially cylindrical insert by metal
injection molding comprising the steps of: providing a primer
insert injection mold to form a substantially cylindrical metal
primer insert, wherein the primer insert mold comprises a top
surface opposite a bottom surface and a substantially cylindrical
coupling element that extends from the bottom surface, a primer
recess in the top surface that extends toward the bottom surface, a
primer flash aperture positioned in the primer recess to extend
through the bottom surface, and a flange that extends
circumferentially about an outer edge of the top surface, wherein
the flange is adapted to receive a polymer overmolding that covers
an circumferential surface and the primer flash hole aperture to
form a primer flash hole; providing a metal injection molding
feedstock comprising a powdered metal and a first binding agent and
a second binding agent; injection molding the metal injection
molding feedstock into the primer insert injection mold to form a
first substantially cylindrical metal primer insert having a first
size; debinding the first substantially cylindrical metal primer
insert to remove the first binding agent; and sintering the first
substantially cylindrical metal primer insert to remove the second
binding agent and form the substantially cylindrical metal primer
insert having a second size.
2. The method of claim 1, wherein the powdered metal comprises
stainless steel, brass, ceramic alloys.
3. The method of claim 1, wherein the powdered metal comprises 102,
174, 201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321,
405, 408, 409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or
601-665 grade stainless steel or Ti6Al4V.
4. The method of claim 1, wherein the second size is about 5
percent to about 30 percent smaller than the first size.
5. The method of claim 1, wherein the second size is about 10
percent to about 20 percent smaller than the first size.
6. The method of claim 1, wherein the second size is about 0.5, 1,
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30 percent smaller than the
first size.
7. The method of claim 1, wherein the substantially cylindrical
insert further comprises a flash hole groove that extends
circumferentially about the primer flash aperture on the top
surface in the primer recess.
8. The method of claim 1, wherein the bottom surface comprises a
circumferential groove.
9. The method of claim 1, wherein the flange is a combination of a
circumferential groove and one or more notches.
10. The method of claim 1, wherein the flange comprises one or more
notches or scallops positioned circumferential.
11. The method of claim 1, wherein the flange comprises 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 notches or scallops
positioned circumferential.
12. The method of claim 1, wherein the powdered metal comprises
2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta;
0-4.0% Mn; 0-2.0% Si and the balance Fe.
13. The method of claim 1, wherein the powdered metal comprises
2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta;
0-3.0% Mn; 0-3.0% Si and the balance Fe.
14. The method of claim 1, wherein the powdered metal comprises
3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta;
0-1.0% Mn; 0-1.0% Si and the balance Fe.
15. The method of claim 1, wherein the powdered metal comprises
10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the
balance Fe.
16. The method of claim 1, wherein the powdered metal comprises
12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe.
17. The method of claim 1, wherein the powdered metal comprises
16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe.
18. The method of claim 1, wherein the powdered metal comprises
3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and
the remainder titanium.
19. The method of claim 1, wherein the powdered metal comprises
about 6% aluminum, about 4% vanadium, about 0.25% iron, about 0.2%
oxygen, and the remainder titanium
20. The substantially cylindrical metal primer insert made by the
method of claim 1.
21. A method of making a substantially cylindrical insert by metal
injection molding comprising the steps of: providing a primer
insert injection mold to form a substantially cylindrical primer
insert, wherein the primer insert mold comprises a top surface
opposite a bottom surface and a substantially cylindrical coupling
element that extends from the bottom surface, a primer recess in
the top surface that extends toward the bottom surface, a primer
flash aperture positioned in the primer recess to extend through
the bottom surface, a flange that extends circumferentially about
an outer edge of the top surface, wherein the flange is adapted to
receive a polymer overmolding that covers an circumferential
surface and the primer flash hole aperture to form a primer flash
hole, and a flash hole groove that extends circumferentially about
the primer flash aperture on the top surface in the primer recess;
providing an injection molding feedstock comprising a powder and a
first binding agent and a second binding agent, wherein the powder
comprises a stainless steel powder, brass powder, alloy powder,
ceramic alloys powder or a combination thereof; injection molding
the injection molding feedstock into the primer insert injection
mold to form a first substantially cylindrical primer insert having
a first size; debinding the first substantially cylindrical primer
insert to remove the first binding agent; and sintering the first
substantially cylindrical metal primer insert to remove the second
binding agent and form the substantially cylindrical primer insert
having a second size, wherein the second size is about 10 percent
to about 25 percent smaller than the first size.
22. The substantially cylindrical metal primer insert made by the
method of claim 21.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
14/320,961, filed 1 Jul. 2014. The contents of which is
incorporated by reference in its entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates in general to the field of
ammunition, specifically to compositions of matter and methods of
making and using substantially cylindrical inserts made by metal
injection molding.
STATEMENT OF FEDERALLY FUNDED RESEARCH
[0003] None.
INCORPORATION-BY-REFERENCE OF MATERIALS FILED ON COMPACT DISC
[0004] None.
BACKGROUND OF THE INVENTION
[0005] Without limiting the scope of the invention, its background
is described in connection with lightweight polymer cartridge
casing ammunition. Conventional ammunition cartridge casings for
rifles and machine guns, as well as larger caliber weapons, are
made from brass, which is heavy, expensive, and potentially
hazardous. There exists a need for an affordable lighter weight
replacement for brass ammunition cartridge cases that can increase
mission performance and operational capabilities. Lightweight
polymer cartridge casing ammunition must meet the reliability and
performance standards of existing fielded ammunition and be
interchangeable with brass cartridge casing ammunition in existing
weaponry. Reliable cartridge casings manufacturing requires
uniformity (e.g., bullet seating, bullet-to-casing fit, casing
strength, etc.) from one cartridge to the next in order to obtain
consistent pressures within the casing during firing prior to
bullet and casing separation to create uniformed ballistic
performance. Plastic cartridge casings have been known for many
years but have failed to provide satisfactory ammunition that could
be produced in commercial quantities with sufficient safety,
ballistic, handling characteristics, and survive physical and
natural conditions to which it will be exposed during the
ammunition's intended life cycle; however, these characteristics
have not been achieved.
[0006] For example, U.S. patent application Ser. No. 11/160,682
discloses a base for a cartridge casing body for an ammunition
article, the base having an ignition device; an attachment device
at one end thereof, the attachment device being adapted to the base
to a cartridge casing body; wherein the base is made from plastic,
ceramic, or a composite material.
[0007] U.S. Pat. No. 7,610,858 discloses an ammunition cartridge
assembled from a substantially cylindrical polymeric cartridge
casing body; and a cylindrical polymeric middle body component with
opposing first and second ends, wherein the first end has a
coupling element that is a mate for the projectile-end coupling
element and joins the first end of the middle body component to the
second end of the bullet-end component, and the second end is the
end of the casing body opposite the projectile end and has a male
or female coupling element; and a cylindrical cartridge casing
head-end component with an essentially closed base end with a
primer hole opposite an open end with a coupling element that is a
mate for the coupling element on the second end of the middle body
and joins the second end of the middle body component to the open
end of the head-end component.
[0008] Shortcomings of the known methods of producing plastic or
substantially plastic ammunition include the possibility of the
projectile being pushed into the cartridge casing, the bullet pull
being too light such that the bullet can fall out, the bullet pull
being too insufficient to create sufficient chamber pressure, the
bullet pull not being uniform from round to round, and portions of
the cartridge casing breaking off upon firing causing the weapon to
jam or damage or danger when subsequent rounds are fired or when
the casing portions themselves become projectiles. To overcome the
above shortcomings, improvements in cartridge case design and
performance polymer materials are needed.
BRIEF SUMMARY OF THE INVENTION
[0009] The present invention provides a method of making a
substantially cylindrical insert by metal injection molding
comprising the steps of: providing a primer insert injection mold
to form a substantially cylindrical metal primer insert, wherein
the primer insert mold comprises a top surface opposite a bottom
surface and a substantially cylindrical coupling element that
extends from the bottom surface, a primer recess in the top surface
that extends toward the bottom surface, a primer flash aperture
positioned in the primer recess to extend through the bottom
surface, and a flange that extends circumferentially about an outer
edge of the top surface, wherein the flange is adapted to receive a
polymer overmolding that covers an circumferential surface and the
primer flash hole aperture to form a primer flash hole; providing a
metal injection molding feedstock comprising a powdered metal and a
first binding agent and a second binding agent; injection molding
the metal injection molding feedstock into the primer insert
injection mold to form a first substantially cylindrical metal
primer insert having a first size; debinding the first
substantially cylindrical metal primer insert to remove the first
binding agent; and sintering the first substantially cylindrical
metal primer insert to remove the second binding agent and form the
substantially cylindrical metal primer insert having a second
size.
[0010] The powdered metal comprises stainless steel, brass, ceramic
alloys. The powdered metal comprises 102, 174, 201, 202, 300, 302,
303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415,
416, 416R, 420, 430, 439, 440, 446 or 601-665 grade stainless
steel. The second size is about 5 percent to about 30 percent
smaller than the first size. The second size is about 10 percent to
about 20 percent smaller than the first size. The second size is
about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 percent
smaller than the first size. The method of claim 1, wherein the
substantially cylindrical insert further comprises a flash hole
groove that extends circumferentially about the primer flash
aperture on the top surface in the primer recess. The bottom
surface comprises a circumferential groove. The flange is a
combination of a circumferential groove and one or more notches.
The flange comprises one or more notches or scallops positioned
circumferential. The flange comprises 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, or 15 notches or scallops positioned
circumferential.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] For a more complete understanding of the features and
advantages of the present invention, reference is now made to the
detailed description of the invention along with the accompanying
figures and in which:
[0012] FIG. 1 depicts a side, cross-sectional view of a polymeric
cartridge case according to one embodiment of the present
invention;
[0013] FIG. 2 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case according to one embodiment of the
present invention;
[0014] FIG. 3 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case lacking the polymer coating over the
flash hole aperture;
[0015] FIGS. 4a and 4b depict images of a catastrophic failure of
the polymeric cartridge case of FIG. 3;
[0016] FIG. 5 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case displaying ribs according to one
embodiment of the present invention;
[0017] FIG. 6 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case displaying ribs according to one
embodiment of the present invention;
[0018] FIG. 7 depicts a side, cross-sectional view of a polymeric
cartridge case having a diffuser according to one embodiment of the
present invention;
[0019] FIG. 8 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case having a diffuser according to one
embodiment of the present invention;
[0020] FIGS. 9a-9h depict the diffuser according to a different
embodiment of the present invention;
[0021] FIG. 10 depicts a perspective view of one embodiment of a
substantially cylindrical primer insert;
[0022] FIG. 11 depicts a cross-sectional view of a substantially
cylindrical primer insert according to one embodiment of the
present invention;
[0023] FIG. 12 depicts a cross-sectional view of the substantially
cylindrical primer insert according to FIG. 11 rotated 90 degrees
relative to FIG. 5; and
[0024] FIGS. 13A-13O depict a perspective view of various different
embodiments of the substantially cylindrical primer insert of the
present invention.
[0025] FIG. 14 depicts an exploded view of the polymeric cartridge
casing;
[0026] FIGS. 15A and 15B depict a view of the substantially
cylindrical open-ended polymeric bullet-end having a shoulder
forming chamber neck and a bullet; and
[0027] FIG. 16 depicts an elevation view of a bullet-end component
of the polymeric cartridge casing; and
[0028] FIG. 17 depicts a side, cross-sectional view of a bullet-end
component of the polymeric cartridge casing.
DETAILED DESCRIPTION OF THE INVENTION
[0029] While the making and using of various embodiments of the
present invention are discussed in detail below, it should be
appreciated that the present invention provides many applicable
inventive concepts that can be embodied in a wide variety of
specific contexts. The specific embodiments discussed herein are
merely illustrative of specific ways to make and use the invention
and do not delimit the scope of the invention.
[0030] Reliable cartridge manufacture requires uniformity from one
cartridge to the next in order to obtain consistent ballistic
performance. Among other considerations, proper bullet seating and
bullet-to-casing fit is required. In this manner, a desired
pressure develops within the casing during firing prior to bullet
and casing separation. Historically, bullets employ a cannelure,
which is a slight annular depression formed in a surface of the
bullet at a location determined to be the optimal seating depth for
the bullet. In this manner, a visual inspection of a cartridge
could determine whether or not the bullet is seated at the proper
depth. Once the bullet is inserted into the casing to the proper
depth, one of two standard procedures is incorporated to lock the
bullet in its proper location. One method is the crimping of the
entire end of the casing into the cannelure. A second method does
not crimp the casing end; rather the bullet is pressure fitted into
the casing.
[0031] The polymeric ammunition cartridges of the present invention
are of a caliber typically carried by soldiers in combat for use in
their combat weapons. The present invention is not limited to the
described caliber and is believed to be applicable to other
calibers as well. This includes various small and medium caliber
munitions, including 5.56 mm, 7.62 mm, 308, 338, 3030, 3006, and
.50 caliber ammunition cartridges, as well as medium/small caliber
ammunition such as 380 caliber, 38 caliber, 9 mm, 10 mm, 20 mm, 25
mm, 30 mm, 40 mm, 45 caliber and the like. The cartridges,
therefore, are of a caliber between about 0.05 and about 5 inches.
Thus, the present invention is also applicable to the sporting
goods industry for use by hunters and target shooters.
[0032] One embodiment of the present invention includes a
substantially cylindrical insert mold for making a substantially
cylindrical insert by metal injection molding comprising: a top
surface opposite a bottom surface and a substantially cylindrical
coupling element that extends from the bottom surface; a primer
recess in the top surface that extends toward the bottom surface; a
primer flash hole positioned in the primer recess to extend through
the bottom surface; and a flange that extends circumferentially
about an outer edge of the top surface.
[0033] Still another embodiment includes a method of forming a
polymeric ammunition cartridge by providing a substantially
cylindrical insert having a top surface opposite a bottom surface
and a substantially cylindrical coupling element that extends from
the bottom surface, a primer recess in the top surface that extends
toward the bottom surface, a primer flash hole positioned in the
primer recess to extend through the bottom surface, and a flange
that extends circumferentially about an outer edge of the top
surface, forming a substantially cylindrical polymeric middle body
comprising a substantially cylindrical polymeric bullet-end and a
substantially cylindrical polymeric coupling end connected by a
powder chamber, connecting the substantially cylindrical polymeric
coupling end to the substantially cylindrical coupling element; and
covering circumferentially an interior surface of the primer flash
hole. The method further includes the step of positioning a
diffuser comprising a diffuser flash hole in the primer recess and
aligning the diffuser flash hole with the primer flash hole.
[0034] FIG. 1 depicts a side, cross-sectional view of a polymeric
cartridge case according to one embodiment of the present
invention. A cartridge 10 suitable for use with high velocity
rifles is shown manufactured with a polymer casing 12 showing a
propellant chamber 14 with projectile (not shown) inserted into the
forward end opening 16. The polymer casing 12 has a substantially
cylindrical open-ended polymeric bullet-end 18 extending from
forward end opening 16 rearward to opposite end 20. The bullet-end
component 18 may be formed with the coupling end 22 formed on the
end 20. The coupling end 22 is shown as a female element, but may
also be configured as a male element in alternate embodiments of
the invention. The forward end of bullet-end component 18 has a
shoulder 24 forming chamber neck 26. The bullet-end component
typically has a wall thickness between about 0.003 and about 0.200
inches and more preferably between about 0.005 and more preferably
between about 0.150 inches about 0.010 and about 0.050 inches.
[0035] The middle body component 28 is connected to a substantially
cylindrical coupling element 30 of the substantially cylindrical
insert 32. The coupling element 30, as shown may be configured as a
male element, however, all combinations of male and female
configurations is acceptable for the coupling elements 30 and the
coupling end 22 in alternate embodiments of the invention. The
coupling end 22 of bullet-end component 18 fits about and engages
the coupling element 30 of a substantially cylindrical insert 32.
The substantially cylindrical insert 32 includes a substantially
cylindrical coupling element 30 extending from a bottom surface 34
that is opposite a top surface 36. Located in the top surface 36 is
a primer recess 38 that extends toward the bottom surface 34. A
primer flash hole 40 is located in the primer flash hole 40 and
extends through the bottom surface 34 into the propellant chamber
14. The coupling end 22 extends the polymer through the primer
flash hole 40 to form an aperture coating 42 while retaining a
passage from the top surface 36 through the bottom surface 34 and
into the propellant chamber 14 to provide support and protection
about the primer flash hole 40. When contacted the coupling end 22
interlocks with the substantially cylindrical coupling element 30,
through the coupling element 30 that extends with a taper to a
smaller diameter at the tip 44 to form a physical interlock between
substantially cylindrical insert 32 and middle body component 28.
The polymer casing 12 also has a substantially cylindrical
open-ended middle body component 28. The middle body component
extends from a forward end opening 16 to the coupling element 22.
The middle body component typically has a wall thickness between
about 0.003 and about 0.200 inches and more preferably between
about 0.005 and more preferably between about 0.150 inches about
0.010 and about 0.050 inches. The bullet-end 16, middle body 18 and
bottom surface 34 define the interior of propellant chamber 14 in
which the powder charge (not shown) is contained. The interior
volume of propellant chamber 14 may be varied to provide the volume
necessary for complete filling of the chamber 14 by the propellant
chosen so that a simplified volumetric measure of propellant can be
utilized when loading the cartridge. Either a particulate or
consolidated propellant can be used.
[0036] The substantially cylindrical insert 32 also has a flange 46
cut therein and a primer recess 38 formed therein for ease of
insertion of the primer (not shown). The primer recess 38 is sized
so as to receive the primer (not shown) in an interference fit
during assembly. A primer flash hole 40 communicates through the
bottom surface 34 of substantially cylindrical insert 32 into the
propellant chamber 14 so that upon detonation of primer (not shown)
the powder in propellant chamber 14 will be ignited.
[0037] The projectile (not shown) is held in place within chamber
case neck 26 at forward opening 16 by an interference fit.
Mechanical crimping of the forward opening 16 can also be applied
to increase the bullet pull force. The bullet (not shown) may be
inserted into place following the completion of the filling of
propellant chamber 14. The projectile (not shown) can also be
injection molded directly onto the forward opening 16 prior to
welding or bonding together using solvent, adhesive, spin-welding,
vibration-welding, ultrasonic-welding or laser-welding techniques.
The welding or bonding increases the joint strength so the casing
can be extracted from the hot gun casing after firing at the
cook-off temperature.
[0038] The bullet-end and bullet components can then be welded or
bonded together using solvent, adhesive, spin-welding,
vibration-welding, ultrasonic-welding or laser-welding techniques.
The welding or bonding increases the joint strength so the casing
can be extracted from the hot gun casing after firing at the
cook-off temperature. An optional first and second annular grooves
(cannelures) may be provided in the bullet-end in the interlock
surface of the male coupling element to provide a snap-fit between
the two components. The cannelures formed in a surface of the
bullet at a location determined to be the optimal seating depth for
the bullet. Once the bullet is inserted into the casing to the
proper depth to lock the bullet in its proper location. One method
is the crimping of the entire end of the casing into the
cannelures.
[0039] The bullet-end and middle body components can then be welded
or bonded together using solvent, adhesive, spin-welding,
vibration-welding, ultrasonic-welding or laser-welding techniques.
The welding or bonding increases the joint strength so the casing
can be extracted from the hot gun casing after firing at the
cook-off temperature.
[0040] FIG. 2 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case according to one embodiment of the
present invention. A portion of a cartridge suitable for use with
high velocity rifles is shown manufactured with a polymer casing 12
showing a propellant chamber 14. The polymer casing 12 has a
substantially cylindrical opposite end 20. The bullet-end component
18 may be formed with the coupling end 22 formed on end 20. The
coupling end 22 is shown as a female element, but may also be
configured as a male element in alternate embodiments of the
invention. The middle body component (not shown) is connected to a
substantially cylindrical coupling element 30 of the substantially
cylindrical insert 32. The coupling element 30, as shown may be
configured as a male element, however, all combinations of male and
female configurations is acceptable for the coupling elements 30
and the coupling end 22 in alternate embodiments of the invention.
The coupling end 22 fits about and engages the coupling element 30
of a substantially cylindrical insert 32. The substantially
cylindrical insert 32 includes a substantially cylindrical coupling
element 30 extending from a bottom surface 34 that is opposite a
top surface 36. Located in the top surface 36 is a primer recess 38
that extends toward the bottom surface 34. A primer flash hole 40
is located in the primer recess 28 and extends through the bottom
surface 34 into the propellant chamber 14. The coupling end 22
extends the polymer through the primer flash hole 40 to form an
aperture coating 42 while retaining a passage from the top surface
36 through the bottom surface 34 and into the propellant chamber 14
to provide support and protection about the primer flash hole 40.
When contacted the coupling end 22 interlocks with the
substantially cylindrical coupling element 30, through the coupling
element 30 that extends with a taper to a smaller diameter at the
tip 44 to form a physical interlock between substantially
cylindrical insert 32 and middle body component 28. The polymer
casing 12 also has a substantially cylindrical open-ended middle
body component 28.
[0041] FIG. 3 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case lacking the aperture coating (not
shown). A portion of a cartridge suitable for use with high
velocity rifles is shown manufactured with a polymer casing (not
shown) showing a powder chamber 14. The polymer casing (not shown)
has a substantially cylindrical opposite end 20. The bullet-end
component (not shown) may be formed with the coupling end 22 formed
on end 20. The coupling end 22 is shown as a female element, but
may also be configured as a male element in alternate embodiments
of the invention. The middle body component (not shown) is
connected to a substantially cylindrical coupling element 30 of the
substantially cylindrical insert 32. The coupling element 30, as
shown may be configured as a male element, however, all
combinations of male and female configurations are acceptable for
the coupling elements 30 and coupling end 22 in alternate
embodiments of the invention. The coupling end 22 fits about and
engages the coupling element 30 of a substantially cylindrical
insert 32. The substantially cylindrical insert 32 includes a
substantially cylindrical coupling element 30 extending from a
bottom surface 34 that is opposite a top surface 36. Located in the
top surface 36 is a primer recess 38 that extends toward the bottom
surface 34. A primer flash hole (not shown) is located in the
primer recess 28 and extends through the bottom surface 34 into the
powder chamber 14. When contacted the coupling end 22 interlocks
with the substantially cylindrical coupling element 30, through the
coupling element 30 that extends with a taper to a smaller diameter
at the tip (not shown) to form a physical interlock between
substantially cylindrical insert 32 also has a flange 46 cut
therein and middle body component (not shown).
[0042] FIGS. 4a and 4b depict images of a catastrophic failure of
the polymeric cartridge case of FIG. 3. Other polymeric cartridge
case was tested and resulted in catastrophic failure with the
rounds blowing the magazine out of the weapon and fragmenting the
metal insert and lodging the polymer case in the chamber. The
examination of the catastrophic failure revealed the tearing of the
polymer at the top of the insert. As a result, in some embodiments
the height of the insert was reduced by 0.020'' to reduce the
tearing and frequency of catastrophic failures. Further
examination, revealed that the polymer at the flash hole of the
base was separating from the insert. One embodiment locks the
polymer into the flash hole by extending the polymer into the flash
hole. In addition, the raised area was removed, the diameter of the
flash hole was opened, and the primer side was counter bored. Other
embodiments may incorporate all, one, or a combination of 2 or more
of these elements to stop the gas from separating the polymer from
the insert that was creating combustion between the insert and the
polymer.
[0043] FIG. 5 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case displaying ribs according to one
embodiment of the present invention. A portion of a cartridge
suitable for use with high velocity rifles is shown manufactured
with a polymer casing (not shown) showing a powder chamber 14. The
polymer casing (not shown) has a substantially cylindrical opposite
end 20. The bullet-end component 18 may be formed with the coupling
end 22 formed on end 20. The coupling end 22 is shown as a female
element, but may also be configured as a male element in alternate
embodiments of the invention. The middle body component (not shown)
is connected to a substantially cylindrical coupling element 30 of
the substantially cylindrical insert 32. The coupling element 30,
as shown may be configured as a male element, however, all
combinations of male and female configurations is acceptable for
coupling elements 30 and coupling end 22 in alternate embodiments
of the invention. The coupling end 22 fits about and engages the
coupling element 30 of a substantially cylindrical insert 32. The
substantially cylindrical insert 32 includes a substantially
cylindrical coupling element 30, extending from a bottom surface 34
that is opposite a top surface 36. Located in the top surface 36 is
a primer recess 38 that extends toward the bottom surface 34. A
primer flash hole 40 is located in the primer recess 28 and extends
through the bottom surface 34 into the powder chamber 14. The
coupling end 22 extends the polymer through the primer flash hole
40 to form an aperture coating 42 while retaining a passage from
the top surface 36 through the bottom surface 34 and into the
powder chamber 14 to provide support and protection about the
primer flash hole 40. When contacted the coupling end 22 interlocks
with the substantially cylindrical coupling element 30, through the
coupling element 30 that extends with a taper to a smaller diameter
at the tip 44 to form a physical interlock between substantially
cylindrical insert 32 also has a flange 46 cut therein and middle
body component 28. The polymer casing (not shown) also has a
substantially cylindrical open-ended middle body component 28. The
substantially cylindrical opposite end 20 or anywhere within the
powder chamber 14 may include one or more ribs 48 on the surface.
The number of ribs 48 will depend on the specific application and
desire of the manufacture but may include 1, 2, 3, 4, 5 6, 7, 8, 9,
10, or more ribs. In the counter bore, the polymer was having
difficulty filling this area due to the fact that the polymer used
has fillers in it, and needed to be reblended during molding. One
embodiment includes six ribs 48 to create turbulence in the flow of
the polymer, thus allowing the material to fill the counter
bore.
[0044] FIG. 6 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case displaying ribs according to one
embodiment of the present invention. One embodiment that reduces
bellowing of the insert includes a shortened insert and angled the
coupling element 30 inside of the insert. In addition, the raised
portion of the polymer at the flash hole was removed, the internal
polymer wall was lowered and angled to match the insert and the
internal ribs were lengthened.
[0045] A portion of a cartridge suitable for use with high velocity
rifles is shown manufactured with a polymer casing (not shown)
showing a powder chamber 14. The polymer casing (not shown) has a
substantially cylindrical opposite end 20. The bullet-end component
(not shown) may be formed with coupling end 22 formed on end 20.
The coupling end 22 is shown as a female element, but may also be
configured as a male element in alternate embodiments of the
invention. The middle body component (not shown) is connected to a
substantially cylindrical coupling element 30 of the substantially
cylindrical insert 32. The coupling element 30, as shown may be
configured as a male element, however, all combinations of male and
female configurations are acceptable for the coupling elements 30
and the coupling end 22 in alternate embodiments of the invention.
The coupling end 22 fits about and engages the coupling element 30
of a substantially cylindrical insert 32. The substantially
cylindrical insert 32 includes a substantially cylindrical coupling
element 30 extending from a bottom surface 34 that is opposite a
top surface 36. Located in the top surface 36 is a primer recess 38
that extends toward the bottom surface 34. A primer flash hole 40
is located in the primer recess 28 and extends through the bottom
surface 34 into the powder chamber 14. The coupling end 22 extends
the polymer through the primer flash hole 40 to form an aperture
coating 42 while retaining a passage from the top surface 36
through the bottom surface 34 and into the powder chamber 14 to
provide support and protection about the primer flash hole 40. When
contacted the coupling end 22 interlocks with the substantially
cylindrical coupling element 30, through the coupling element 30
that extends with a taper to a smaller diameter at the tip 44 to
form a physical interlock between substantially cylindrical insert
32 and middle body component 28. The polymer casing (not shown)
also has a substantially cylindrical open-ended middle body
component 28. The substantially cylindrical opposite end 20 or
anywhere within the powder chamber 14 may include one or more ribs
48 on the surface. The number of ribs 48 will depend on the
specific application and desire of the manufacture but may include
1, 2, 3, 4, 5 6, 7, 8, 9, 10, or more ribs. In the counter bore,
the polymer was having difficulty filling this area due to the fact
that the polymer used has fillers in it, and needed to be reblended
during molding. One embodiment includes six ribs 48 to create
turbulence in the flow of the polymer, thus allowing the material
to fill the counter bore. Another embodiment of the present
invention is a shortened insert and angled coupling element 30
inside of the insert. In addition, raised portions of the polymer
at the flash hole, lowered and angled the internal polymer wall to
match the insert and lengthened the internal ribs.
[0046] FIG. 7 depicts a side, cross-sectional view of a polymeric
cartridge case having a diffuser according to one embodiment of the
present invention. The diffuser (not shown) is a device that is
used to divert the affects of the primer off of the polymer and
directing it to the flash hole. The affects being the impact from
igniting the primer as far as pressure and heat. A cartridge 10
suitable for use with high velocity rifles is shown manufactured
with a polymer casing (not shown) showing a powder chamber 14 with
projectile (not shown) inserted into the forward end opening 16.
The polymer casing (not shown) has a substantially cylindrical
open-ended polymeric bullet-end 18 extending from forward end
opening 16 rearward to the opposite end 20. The bullet-end
component (not shown) may be formed with the coupling end 22 formed
on the end 20. The coupling end 22 is shown as a female element,
but may also be configured as a male element in alternate
embodiments of the invention. The forward end of bullet-end
component 18 has a shoulder 24 forming chamber neck 26.
[0047] The middle body component 28 is connected to a substantially
cylindrical coupling element 30 of the substantially cylindrical
insert 32. The coupling element 30, as shown may be configured as a
male element, however, all combinations of male and female
configurations is acceptable for the coupling elements 30 and the
coupling end 22 in alternate embodiments of the invention. The
coupling end 22 of bullet-end component 18 fits about and engages
the coupling element 30 of a substantially cylindrical insert 32.
The substantially cylindrical insert 32 includes a substantially
cylindrical coupling element 30 extending from a bottom surface 34
that is opposite a top surface 36. Located in the top surface 36 is
a primer recess 38 that extends toward the bottom surface 34. A
primer flash hole 40 is located in the primer recess 28 and extends
through the bottom surface 34 into the powder chamber 14. The
coupling end 22 extends the polymer through the primer flash hole
40 to form an aperture coating 42 while retaining a passage from
the top surface 36 through the bottom surface 34 and into the
powder chamber 14 to provides support and protection about the
primer flash hole 40. When contacted the coupling end 22 interlocks
with the substantially cylindrical coupling element 30, through the
coupling element 30 that extends with a taper to a smaller diameter
at the tip 44 to form a physical interlock between substantially
cylindrical insert 32 also has a flange 46 cut therein and middle
body component 28. The polymer casing 12 also has a substantially
cylindrical open-ended middle body component 28. The middle body
component extends from a forward end opening 16 to the coupling
element 22. Located in the top surface 36 is a primer recess 38
that extends toward the bottom surface 34 with a diffuser (not
shown) positioned in the primer recess 38. The diffuser (not shown)
includes a diffuser aperture (not shown) that aligns with the
primer flash hole 40. The diffuser (not shown) is a device that is
used to divert the affects of the primer (not shown) off of the
polymer. The affects being the impact from igniting the primer as
far as pressure and heat to divert the energy of the primer off of
the polymer and directing it to the flash hole.
[0048] FIG. 8 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case having a diffuser according to one
embodiment of the present invention. A portion of a cartridge
suitable for use with high velocity rifles is shown manufactured
with a polymer casing (not shown) showing a powder chamber 14. The
polymer casing (not shown) has a substantially cylindrical opposite
end 20. The bullet-end component (not shown) may be formed with the
coupling end 22 formed on the end 20. The coupling end (not shown)
is shown as a female element, but may also be configured as a male
element in alternate embodiments of the invention. The middle body
component (not shown) is connected to a substantially cylindrical
coupling element 30 of the substantially cylindrical insert 32. The
coupling element 30, as shown may be configured as a male element,
however, all combinations of male and female configurations are
acceptable for the coupling elements 30 and the coupling end (not
shown) in alternate embodiments of the invention. The coupling end
(not shown) fits about and engages the coupling element 30 of a
substantially cylindrical insert 32. The substantially cylindrical
insert 32 includes a substantially cylindrical coupling element 30
extending from a bottom surface (not shown) that is opposite a top
surface 36. Located in the top surface 36 is a primer recess 38
that extends toward the bottom surface (not shown). A primer flash
hole 40 extends through the bottom surface (not shown) into the
powder chamber 14. The coupling end (not shown) extends the polymer
through the primer flash hole 40 to form an aperture coating 42
while retaining a passage from the top surface 36 through the
bottom surface (not shown) and into the powder chamber 14 to
provides support and protection about the primer flash hole 40.
When contacted the coupling end (not shown) interlocks with the
substantially cylindrical coupling element 30, through the coupling
element 30 that extends with a taper to a smaller diameter at the
tip 44 to form a physical interlock between substantially
cylindrical insert 32 also has a flange 46 cut therein and middle
body component 28. The polymer casing (not shown) also has a
substantially cylindrical open-ended middle body component 28.
Located in the top surface 36 is a primer recess 38 that extends
toward the bottom surface (not shown) with a diffuser 50 positioned
in the primer recess 38. The diffuser (not shown) includes a
diffuser aperture 52 and a diffuser aperture extension 54 that
aligns with the primer flash hole 40. The diffuser 50 is a device
that is used to divert the affects of the primer (not shown) off of
the polymer. The affects being the impact from igniting the primer
as far as pressure and heat to divert the energy of the primer off
of the polymer and directing it to the flash hole. The diffuser 50
can be between 0.004 to 0.010 inches in thickness and made from
half hard brass. For example, the diffuser 50 can be between 0.005
inches thick for a 5.56 diffuser 50. The outer diameter of the
diffuser for a 5.56 or 223 case is 0.173 and the inner diameter is
0.080. The Diffuser could be made of any material that can
withstand the energy from the ignition of the primer. This would
include steel, stainless, cooper, aluminum or even an engineered
resin that was injection molded or stamped. The Diffuser can be
produce in T shape by drawing the material with a stamping and draw
die. In the T Diffuser the center ring can be 0.005 to 0.010 tall
and the outer diameter is 0.090 and the inner diameter 0.080.
[0049] FIGS. 9a-9h depict different embodiment of the diffuser of
the present invention.
[0050] FIG. 10 depicts a perspective view of a substantially
cylindrical primer insert according to one embodiment of the
present invention. The substantially cylindrical primer insert 32
has an optional flange 46 cut therein and a primer recess (not
shown) formed therein for ease of insertion of the primer recess
(not shown). The flange 46 extends circumferentially about the
outer edge of the substantially cylindrical primer insert 32. The
primer recess (not shown) is sized so as to receive the primer in
an interference fit during assembly. A series of notches 42 are
placed along the exterior circumference of substantially
cylindrical primer insert 32 circling the primer recess (not shown)
between flange 46 and coupling element 30. The coupling element 30
extends from a bottom surface (not shown) to a coupling tip 44. The
design, shape and number of notches 42 will depend on the specific
application and desire of the manufacture but may include 1, 2, 3,
4, 5 6, 7, 8, 9, 10, or more notches.
[0051] FIG. 11 depicts a cross-sectional view of a substantially
cylindrical primer insert 32 according to one embodiment of the
present invention. The substantially cylindrical primer insert 32
has a flange 46 cut that extends circumferentially about an outer
edge of the top surface 36. A primer recess 38 in the top surface
36 extends from top surface 36 towards a bottom surface 34. The
substantially cylindrical primer insert 32 also includes a coupling
element 30 that extends from the bottom surface 34 to a coupling
tip 44. A primer flash hole 40 is positioned in the primer recess
38 and extends through the bottom surface 34 into an insert opening
48 in the coupling element 30. When contacted with the rest of the
cartridge (not shown), the cartridge interlocks with the coupling
element 30.
[0052] The metal injection molding process of making the
substantially cylindrical primer insert 32 mold shown is made in
the shape of the substantially cylindrical primer insert 32
includes the desired profile of the primer recess 38. The
substantially cylindrical primer insert 32 includes a coupling
element 30 extending from a bottom surface 34 that is opposite a
top surface 36. Located in the top surface 36 is a primer recess 38
that extends toward the bottom surface 34. A primer flash hole 38
is located in the substantially cylindrical primer insert 32 and
extends through the bottom surface 34 into the insert opening
48.
[0053] FIG. 12 depicts a rotated, cross-sectional view of a portion
of the substantially cylindrical primer insert 32 according to one
embodiment of the present invention. The substantially cylindrical
primer insert 32 has a flange 46 cut that extends circumferentially
about an outer edge of the top surface 36. A primer recess 38 in
the top surface 36 extends from top surface 36 towards a bottom
surface 34. A notch 42 adjacent to the primer recess 38 extends
from flange 46 towards bottom surface 34. The gas generator insert
32 also includes a coupling element 30 that extends from the bottom
surface 34 to a coupling tip 44. A primer flash hole 40 is
positioned in the primer recess 38 and extends through the bottom
surface 34 into an insert opening 48.
[0054] FIGS. 13A-13O depict perspective views of a substantially
cylindrical primer inserts according to various embodiments of the
present invention. FIGS. 13A-13O illustrate the shape of the
substantially cylindrical primer insert; however other shapes and
variations are contemplated. The flange on the substantially
cylindrical primer insert is optional and the notches can be of any
number, shape, or design including scallop shaped, wing shaped,
prism shaped, rectangular shaped and the like.
[0055] FIG. 13A shows a perspective view of an embodiment of the
substantially cylindrical primer insert 32 wherein the notches 42
is a triangular prism extending from flange 46 towards bottom
surface 34 (not shown). FIG. 13B shows another embodiment of
substantially cylindrical primer insert 32 with an increased number
of notches 42 as triangular prisms positioned on flange 46. The
number of notches 42 can be tailored to the specific application
and need of the manufacturer.
[0056] FIG. 13C shows a perspective view of an embodiment of the
substantially cylindrical primer insert 32 wherein the notches 42
are redesigned as a band 50. Band 50 provides the same lateral
support as notches 42 around the primer recess 38 (not shown) and
is also positioned on flange 46.
[0057] FIG. 13D shows a perspective view of an embodiment of the
substantially cylindrical primer insert 32 wherein the notches 42
are redesigned into the shape of a laterally extruded half
cylinder. The notches 42 are positioned on flange 46 and extend
toward bottom surface 34 (not shown). FIGS. 13E and 13F show
additional variations embodiment of the substantially cylindrical
primer insert 32 with different numbers of notches 42 positioned on
flange 46. The different embodiments show different spacing between
each of the notches 42. The number of notches 42 and the spacing
between each of them can be tailored to the specific
application.
[0058] FIG. 13G shows a perspective view of another embodiment of
the substantially cylindrical primer insert 32 with wider laterally
extruded half cylinder notches 42 positioned on flange 46. The size
and design of the notches 42 as well as its placement and the
spacing between them can be tailored to the specific
application.
[0059] FIG. 13H shows a perspective view of another embodiment of a
substantially cylindrical primer insert 32 where the notches 42 are
scallop shaped and continuous. There is no spacing between the
series of connected notches 42 positioned on top of flange 46. The
connected scallop shaped notches 42 surround the outer casing of
the primer recess 38 (not shown). FIG. 13I shows another embodiment
of the substantially cylindrical primer insert 32 with continuous
scallop notches 42 with a different number of scallop notches 42
positioned on flange 46. The number and width of notches 42 can be
tailored to the specific application.
[0060] FIGS. 13J and 13K show a perspective view of different
embodiment of the substantially cylindrical primer insert 32
wherein the notches 42 are scallop shaped and continuous, but the
coupling element 30 are of varying lengths or height. FIG. 13J
shows an embodiment with a shorter coupling element 30. FIG. 13K
shows an embodiment with a taller coupling element 30 of the
substantially cylindrical primer insert. The height or length of
coupling element 30 can be tailored to the specific application and
need.
[0061] FIG. 13L shows another embodiment of the substantially
cylindrical primer insert 32 wherein the notches 42 is scallop
shaped and continuous, but has a smaller curvature profile. The
size, length, numbering, and curvature of the notches 42 can be
tailored to the specific application and need.
[0062] FIG. 13M shows another embodiment of the substantially
cylindrical primer insert 32 wherein there are no notches 42
positioned on flange 46.
[0063] FIG. 13N shows another embodiment of the substantially
cylindrical primer insert 32 wherein notches 42 are replaced by
band 50, but band 50 includes a series of bands with different
profiles and heights. The thickness, number, height, and profile of
band 50 positioned on flange 46 and wrapping around primer recess
38 (not shown) can be tailored to the specific application and need
of the manufacturer.
[0064] FIG. 13O shows another embodiment of the substantially
cylindrical primer insert 32 wherein notches 42 are a series of
different shapes with different thicknesses and designs, as well as
different spacing in between each and no set number when positioned
on flange 46. The number, shape, design, and spacing of notches 42
can be tailored to the specific application and is not limited to
recurring similar shapes or designs.
[0065] Another embodiment of the present invention having a top
surface opposite a bottom surface and a coupling element that
extends from the bottom surface away from the top surface, a primer
recess in the top surface that extends toward the bottom surface, a
primer flash hole positioned in the primer recess to extend through
the bottom surface, and a flange that extends circumferentially
about an outer edge of the top surface.
[0066] For example, the metal injection molding process, which
generally involves mixing fine metal powders with binders to form a
feedstock that is injection molded into a closed mold, may be used
to form a substantially cylindrical insert. After ejection from the
mold, the binders are chemically or thermally removed from the
substantially cylindrical insert so that the part can be sintered
to high density. During the sintering process, the individual metal
particles metallurgically bond together as material diffusion
occurs to remove most of the porosity left by the removal of the
binder.
[0067] The raw materials for metal injection molding are metal
powders and a thermoplastic binder. There are at least two Binders
included in the blend, a primary binder and a secondary binder.
This blended powder mix is worked into the plasticized binder at
elevated temperature in a kneader or shear roll extruder. The
intermediate product is the so-called feedstock. It is usually
granulated with granule sizes of several millimeters. In metal
injection molding, only the binders are heated up, and that is how
the metal is carried into the mold cavity whereas,
[0068] Parts are molded until they feel that the cavity has been
filled. Both mold design factors such as runner and gate size, gate
placement, venting and molding parameters set on the molding
machine affect the molded part. A helium Pycnometer can determine
if there are voids trapped inside the parts. During molding, you
have a tool that can be used to measure the percent of theoretical
density achieved on the "Green" or molded part. By crushing the
measured "green" molded part back to powder, you can now confirm
the percent of air (or voids) trapped in the molded part. To
measure this, the density of the molded part should be measured in
the helium Pycnometer and compared to the theoretical density of
the feedstock. Then, take the same molded part that was used in the
density test and crush it back to powder. If this granulate shows a
density of more than 100% of that of the feedstock, then some of
the primary binders have been lost during the molding process. The
molding process needs to be corrected because using this process
with a degraded feedstock will result in a larger shrinkage and
result in a part smaller than that desired. It is vital to be sure
that your molded parts are completely filled before continuing the
manufacturing process for debinding and sintering. The helium
Pycnometer provides this assurance. Primary debinding properly
debound parts are extremely important to establish the correct
sintering profile. The primary binder must be completely removed
before attempting to start to remove the secondary binder as the
secondary binder will travel through the pores created by the
extraction of the primary binder. Primary debinding techniques
depend on the feedstock type used to make the parts. However the
feedstock supplier knows the amount of primary binders that have
been added and should be removed before proceeding to the next
process step. The feedstock supplier provides a minimum "brown
density" that must be achieved before the parts can be moved into a
furnace for final debinding and sintering. This minimum brown
density will take into account that a small amount of the primary
binder remnant may be present and could be removed by a suitable
hold during secondary debinding and sintering. The sintering
profile should be adjusted to remove the remaining small percent of
primary binder before the removal of the secondary binder. Most
external feedstock manufacturers provide only a weight loss percent
that should be obtained to define suitable debinding. Solvent
debound parts must be thoroughly dried, before the helium
Pycnometer is used to determine the "brown" density so that the
remnant solvent in the part does not affect the measured density
value. When the feedstock manufacturer gives you the theoretical
density of the "brown" or debound part, can validate the percent of
debinding that has been achieved. Most Metal Injection Molding
(MIM) operations today perform the secondary debinding and
sintering in the same operation. Every MIM molder has gates and
runners left over from molding their parts. So, you will be able to
now re-use your gates and runners with confidence that they will
shrink correctly after sintering. If the feedstock producers have
given you the actual and theoretical densities of their feedstock,
you can easily measure the densities of the gates and runners and
compare the results to the values supplied. Once the regrind
densities are higher than that required to maintain the part
dimensions, the regrinds are no longer reusable.
[0069] Feedstock in accordance with the present invention may be
prepared by blending the powdered metal with the binder and heating
the blend to form a slurry. Uniform dispersion of the powdered
metal in the slurry may be achieved by employing high shear mixing.
The slurry may then be cooled to ambient temperature and then
granulated to provide the feedstock for the metal injection
molding.
[0070] The amount of powdered metal and binder in the feedstock may
be selected to optimize moldability while insuring acceptable green
densities. In one embodiment, the feedstock used for the metal
injection molding portion of the invention may include at least
about 40 percent by weight powdered metal, in another about 50
percent by weight powdered metal or more. In one embodiment, the
feedstock includes at least about 60 percent by weight powdered
metal, preferably about 65 percent by weight or more powdered
metal. In yet another embodiment, the feedstock includes at least
about 75 percent by weight powdered metal. In yet another
embodiment, the feedstock includes at least about 80 percent by
weight powdered metal. In yet another embodiment, the feedstock
includes at least about 85 percent by weight powdered metal. In yet
another embodiment, the feedstock includes at least about 90
percent by weight powdered metal.
[0071] The binding agent may be any suitable binding agent that
does not destroy or interfere with the powdered metals. The binder
may be present in an amount of about 50 percent or less by weight
of the feedstock. In one embodiment, the binder is present in an
amount ranging from 10 percent to about 50 percent by weight. In
another embodiment, the binder is present in an amount of about 25
percent to about 50 percent by weight of the feedstock. In another
embodiment, the binder is present in an amount of about 30 percent
to about 40 percent by weight of the feedstock. In one embodiment,
the binder is an aqueous binder. In another embodiment, the binder
is an organic-based binder. Examples of binders include, but are
not limited to, thermoplastic resins, waxes, and combinations
thereof. Non-limiting examples of thermoplastic resins include
polyolefins such as acrylic polyethylene, polypropylene,
polystyrene, polyvinyl chloride, polyethylene carbonate,
polyethylene glycol, and mixtures thereof. Suitable waxes include,
but are not limited to, microcrystalline wax, bee wax, synthetic
wax, and combinations thereof
[0072] Examples of suitable powdered metals for use in the
feedstock include, but are not limited to: stainless steel
including martensitic and austenitic stainless steel, steel alloys,
tungsten alloys, soft magnetic alloys such as iron, iron-silicon,
electrical steel, iron-nickel (50Ni-50F3), low thermal expansion
alloys, or combinations thereof. In one embodiment, the powdered
metal is a mixture of stainless steel, brass and tungsten alloy.
The stainless steel used in the present invention may be any 1
series carbon steels, 2 series nickel steels, 3 series
nickel-chromium steels, 4 series molybdenum steels, series chromium
steels, 6 series chromium-vanadium steels, 7 series tungsten
steels, 8 series nickel-chromium-molybdenum steels, or 9 series
silicon-manganese steels, e.g., 102, 174, 201, 202, 300, 302, 303,
304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 416, 420,
430, 439, 440, 446 or 601-665 grade stainless steel.
[0073] As known to those of ordinary skill in the art, stainless
steel is an alloy of iron and at least one other component that
imparts corrosion resistance. As such, in one embodiment, the
stainless steel is an alloy of iron and at least one of chromium,
nickel, silicon, molybdenum, or mixtures thereof. Examples of such
alloys include, but are not limited to, an alloy containing about
1.5 to about 2.5 percent nickel, no more than about 0.5 percent
molybdenum, no more than about 0.15 percent carbon, and the balance
iron with a density ranging from about 7 g/cm.sup.3 to about 8
g/cm.sup.3; an alloy containing about 6 to about 8 percent nickel,
no more than about 0.5 percent molybdenum, no more than about 0.15
percent carbon, and the balance iron with a density ranging from
about 7 g/cm.sup.3 to about 8 g/cm.sup.3; an alloy containing about
0.5 to about 1 percent chromium, about 0.5 percent to about 1
percent nickel, no more than about 0.5 percent molybdenum, no more
than about 0.2 percent carbon, and the balance iron with a density
ranging from about 7 g/cm.sup.3 to about 8 g/cm.sup.3; an alloy
containing about 2 to about 3 percent nickel, no more than about
0.5 percent molybdenum, about 0.3 to about 0.6 percent carbon, and
the balance iron with a density ranging from about 7 g/cm.sup.3 to
about 8 g/cm.sup.3; an alloy containing about 6 to about 8 percent
nickel, no more than about 0.5 percent molybdenum, about 0.2 to
about 0.5 percent carbon, and the balance iron with a density
ranging from about 7 g/cm.sup.3 to about 8 g/cm.sup.3; an alloy
containing about 1 to about 1.6 percent chromium, about 0.5 percent
or less nickel, no more than about 0.5 percent molybdenum, about
0.9 to about 1.2 percent carbon, and the balance iron with a
density ranging from about 7 g/cm.sup.3 to about 8 g/cm.sup.3; and
combinations thereof
[0074] Suitable tungsten alloys include an alloy containing about
2.5 to about 3.5 percent nickel, about 0.5 percent to about 2.5
percent copper or iron, and the balance tungsten with a density
ranging from about 17.5 g/cm.sup.3 to about 18.5 g/cm.sup.3; about
3 to about 4 percent nickel, about 94 percent tungsten, and the
balance copper or iron with a density ranging from about 17.5
g/cm.sup.3 to about 18.5 g/cm.sup.3; and mixtures thereof.
[0075] In addition, the binders may contain additives such as
antioxidants, coupling agents, surfactants, elasticizing agents,
dispersants, and lubricants as disclosed in U.S. Pat. No.
5,950,063, which is hereby incorporated by reference in its
entirety. Suitable examples of antioxidants include, but are not
limited to thermal stabilizers, metal deactivators, or combinations
thereof. In one embodiment, the binder includes about 0.1 to about
2.5 percent by weight of the binder of an antioxidant. Coupling
agents may include but are not limited to titanate, aluminate,
silane, or combinations thereof. Typical levels range between 0.5
and 15% by weight of the binder.
[0076] The polymeric and composite casing components may be
injection molded. Polymeric materials for the bullet-end and middle
body components must have propellant compatibility and resistance
to gun cleaning solvents and grease, as well as resistance to
chemical, biological and radiological agents. The polymeric
materials must have a temperature resistance higher than the
cook-off temperature of the propellant, typically about 320.degree.
F. The polymeric materials must have elongation-to-break values
that to resist deformation under interior ballistic pressure as
high as 60,000 psi in all environments (temperatures from about -65
to about 320.degree. F. and humidity from 0 to 100% relative
humidity). According to one embodiment, the middle body component
is either molded onto or snap-fit to the casing head-end component
after which the bullet-end component is snap-fit or interference
fit to the middle body component. The components may be formed from
high-strength polymer, composite or ceramic.
[0077] Examples of suitable high strength polymers include
composite polymer material including a tungsten metal powder, nylon
6/6, nylon 6, and glass fibers; and a specific gravity in a range
of 3-10. The tungsten metal powder may be 50%-96% of a weight of
the bullet body. The polymer material also includes about 0.5-15%,
preferably about 1-12%, and most preferably about 2-9% by weight,
of nylon 6/6, about 0.5-15%, preferably about 1-12%, and most
preferably about 2-9% by weight, of nylon 6, and about 0.5-15%,
preferably about 1-12%, and most preferably about 2-9% by weight,
of glass fibers. It is most suitable that each of these ingredients
be included in amounts less than 10% by weight. The cartridge
casing body may be made of a modified ZYTEL.RTM. resin, available
from E.I. DuPont De Nemours Co., a modified 612 nylon resin,
modified to increase elastic response.
[0078] Examples of suitable polymers include polyurethane
prepolymer, cellulose, fluoro-polymer, ethylene inter-polymer alloy
elastomer, ethylene vinyl acetate, nylon, polyether imide,
polyester elastomer, polyester sulfone, polyphenyl amide,
polypropylene, polyvinylidene fluoride or thermoset polyurea
elastomer, acrylics, homopolymers, acetates, copolymers,
acrylonitrile-butadinen-styrene, thermoplastic fluoro polymers,
inomers, polyamides, polyamide-imides, polyacrylates,
polyatherketones, polyaryl-sulfones, polybenzimidazoles,
polycarbonates, polybutylene, terephthalates, polyether imides,
polyether sulfones, thermoplastic polyimides, thermoplastic
polyurethanes, polyphenylene sulfides, polyethylene, polypropylene,
polysulfones, polyvinylchlorides, styrene acrylonitriles,
polystyrenes, polyphenylene, ether blends, styrene maleic
anhydrides, polycarbonates, allyls, aminos, cyanates, epoxies,
phenolics, unsaturated polyesters, bismaleimides, polyurethanes,
silicones, vinylesters, or urethane hybrids. Examples of suitable
polymers also include aliphatic or aromatic polyamide,
polyeitherimide, polysulfone, polyphenylsulfone, poly-phenylene
oxide, liquid crystalline polymer and polyketone. Examples of
suitable composites include polymers such as polyphenylsulfone
reinforced with between about 30 and about 70 weight percent, and
preferably up to about 65 weight percent of one or more reinforcing
materials selected from glass fiber, ceramic fiber, carbon fiber,
mineral fillers, organo nanoclay, or carbon nanotube. Preferred
reinforcing materials, such as chopped surface-treated E-glass
fibers provide flow characteristics at the above-described loadings
comparable to unfilled polymers to provide a desirable combination
of strength and flow characteristics that permit the molding of
head-end components. Composite components can be formed by
machining or injection molding. Finally, the cartridge case must
retain sufficient joint strength at cook-off temperatures. More
specifically, polymers suitable for molding of the projectile-end
component have one or more of the following properties: Yield or
tensile strength at -65.degree. F.>10,000 psi
Elongation-to-break at -65.degree. F.>15% Yield or tensile
strength at 73.degree. F.>8,000 psi Elongation-to-break at
73.degree. F.>50% Yield or tensile strength at 320.degree.
F.>4,000 psi Elongation-to-break at 320.degree. F.>80%.
Polymers suitable for molding of the middle-body component have one
or more of the following properties: Yield or tensile strength at
-65.degree. F.>10,000 psi Yield or tensile strength at
73.degree. F.>8,000 psi Yield or tensile strength at 320.degree.
F.>4,000 psi.
[0079] Commercially available polymers suitable for use in the
present invention thus include polyphenylsulfones; copolymers of
polyphenylsulfones with polyether-sulfones or polysulfones;
copolymers and blends of polyphenylsulfones with polysiloxanes;
poly(etherimide-siloxane); copolymers and blends of polyetherimides
and polysiloxanes, and blends of polyetherimides and
poly(etherimide-siloxane) copolymers; and the like. Particularly
preferred are polyphenylsulfones and their copolymers with
poly-sulfones or polysiloxane that have high tensile strength and
elongation-to-break to sustain the deformation under high interior
ballistic pressure. Such polymers are commercially available, for
example, RADEL.RTM. R5800 polyphenylesulfone from Solvay Advanced
Polymers. The polymer can be formulated with up to about 10 wt % of
one or more additives selected from internal mold release agents,
heat stabilizers, anti-static agents, colorants, impact modifiers
and UV stabilizers.
[0080] The polymers of the present invention can also be used for
conventional two-piece metal-plastic hybrid cartridge case designs
and conventional shotgun shell designs. One example of such a
design is an ammunition cartridge with a one-piece substantially
cylindrical polymeric cartridge casing body with an open
projectile-end and an end opposing the projectile-end with a male
or female coupling element; and a cylindrical metal cartridge
casing head-end component with an essentially closed base end with
a primer hole opposite an open end having a coupling element that
is a mate for the coupling element on the opposing end of the
polymeric cartridge casing body joining the open end of the
head-end component to the opposing end of the polymeric cartridge
casing body. The high polymer ductility permits the casing to
resist breakage.
[0081] One embodiment includes a 2 cavity prototype mold having an
upper portion and a base portion for a 5.56 case having a metal
insert over-molded with a Nylon 6 (polymer) based material. In this
embodiment the polymer in the base includes a lip or flange to
extract the case from the weapon. One 2-cavity prototype mold to
produce the upper portion of the 5.56 case can be made using a
stripper plate tool using an Osco hot spur and two subgates per
cavity. Another embodiment includes a subsonic version, the
difference from the standard and the subsonic version is the walls
are thicker thus requiring less powder. This will decrease the
velocity of the bullet thus creating a subsonic round.
[0082] The extracting inserts is used to give the polymer case a
tough enough ridge and groove for the weapons extractor to grab and
pull the case out the chamber of the gun. The extracting insert is
made of 17-4 stainless steel that is hardened to 42-45 rc. The
insert may be made of aluminum, brass, cooper, steel or even an
engineered resin with enough tensile strength.
[0083] The insert is over molded in an injection molded process
using a nano clay particle filled Nylon material. The inserts can
be machined or stamped. In addition, an engineered resin able to
withstand the demand on the insert allows injection molded and/or
even transfer molded.
[0084] One of ordinary skill in the art will know that many
propellant types and weights can be used to prepare workable
ammunition and that such loads may be determined by a careful trial
including initial low quantity loading of a given propellant and
the well known stepwise increasing of a given propellant loading
until a maximum acceptable load is achieved. Extreme care and
caution is advised in evaluating new loads. The propellants
available have various burn rates and must be carefully chosen so
that a safe load is devised.
[0085] The components may be made of polymeric compositions,
metals, ceramics, alloys, or combinations and mixtures thereof. In
addition, the components may be mixed and matched with one or more
components being made of different materials. For example, the
middle body component (not shown) may be polymeric; the bullet-end
component 18 may be polymeric; and a substantially cylindrical
insert (not shown) may be metal. Similarly, the middle body
component (not shown) may be polymeric; the bullet-end component 18
may be metal; and a substantially cylindrical insert (not shown)
may be an alloy. The middle body component (not shown) may be
polymeric; the bullet-end component 18 may be an alloy; and a
substantially cylindrical insert (not shown) may be an alloy. The
middle body component (not shown); the bullet-end component 18;
and/or the substantially cylindrical insert may be made of a metal
that is formed by a metal injection molding process.
[0086] FIG. 14 depicts an exploded view of the polymeric cartridge
casing. A cartridge 10 suitable for use with high velocity rifles
is shown manufactured with a middle body component 28 having a
substantially cylindrical open-ended polymeric bullet-end 18
extending from forward end opening 16 rearward to opposite end 20.
A portion of a cartridge suitable for use with high velocity rifles
is shown manufactured with a polymer casing 12 showing a powder
chamber 14. The polymer casing 12 has a substantially cylindrical
opposite end 20. The bullet-end component 18 may be formed with the
coupling end 22 formed on end 20. The coupling end 22 is shown as a
female element, but may also be configured as a male element in
alternate embodiments of the invention. The middle body component
28 is connected to a substantially cylindrical coupling element 30
of the substantially cylindrical insert 32. The substantially
cylindrical open-ended polymeric bullet-end 18 has a shoulder 24
forming chamber neck 26 and a bullet 56 inserted therein. The
substantially cylindrical insert 32 also has a flange 46 cut
therein and a primer recess (not shown) formed therein for ease of
insertion of the primer (not shown). When contacted the coupling
end 22 interlocks with the substantially cylindrical coupling
element 30, through the coupling element 30 that extends with a
taper to a smaller diameter at the tip 44 to form a physical
interlock between substantially cylindrical insert 32 and middle
body component 28. In one embodiment of the present invention, the
substantially cylindrical insert 32 may be made of a metal that is
formed by a metal injection molding process. The model design may
be seen herein.
[0087] The molded substantially cylindrical insert 32 is then bound
to the middle body component 28. In the metal injection molding
process of making the substantially cylindrical insert 32 a mold is
made in the shape of the substantially cylindrical insert 32
including the desired profile of the primer recess (not shown). The
substantially cylindrical insert 32 includes a substantially
cylindrical coupling element 30 extending from a bottom surface 34
that is opposite a top surface (not shown). Located in the top
surface (not shown) is a primer recess (not shown) that extends
toward the bottom surface 34. A primer flash hole (not shown) is
located in the substantially cylindrical insert 32 and extends
through the bottom surface 34 into the powder chamber 14. The
coupling end (not shown) extends through the primer flash hole (not
shown) to form an aperture coating (not shown) while retaining a
passage from the top surface (not shown) through the bottom surface
(not shown) and into the powder chamber 14 to provides support and
protection about the primer flash hole (not shown). When contacted
the coupling end (not shown) interlocks with the substantially
cylindrical coupling element 30, through the coupling element 30
that extends with a taper to a smaller diameter at the tip (not
shown) to form a physical interlock between substantially
cylindrical insert 32 and middle body component 28.
[0088] For example, the metal injection molding process, which
generally involves mixing fine metal powders with binders to form a
feedstock that is injection molded into a closed mold, may be used
to form a substantially cylindrical insert. After ejection from the
mold, the binders are chemically or thermally removed from the
substantially cylindrical insert so that the part can be sintered
to high density. During the sintering process, the individual metal
particles metallurgically bond together as material diffusion
occurs to remove most of the porosity left by the removal of the
binder.
[0089] The raw materials for metal injection molding are metal
powders and a thermoplastic binder. There are at least two Binders
included in the blend, a primary binder and a secondary binder.
This blended powder mix is worked into the plasticized binder at
elevated temperature in a kneader or shear roll extruder. The
intermediate product is the so-called feedstock. It is usually
granulated with granule sizes of several millimeters. In metal
injection molding, only the binders are heated up, and that is how
the metal is carried into the mold cavity.
[0090] In preparing a Feedstock, it is important first to measure
the actual density of each lot of both the metal powders and
binders. This is extremely important especially for the metal
powders in that each lot will be different based on the actual
chemistry of that grade of powder. For example, 316L is comprised
of several elements, such as Fe, Cr, Ni, Cu, Mo, P, Si, S and C. In
order to be rightfully called a 316L, each of these elements must
meet a minimum and maximum percentage weight requirement as called
out in the relevant specification. Hence the variation in the
chemistry within the specification results in a significant density
variation within the acceptable composition range. Depending on the
lot received from the powder producer, the density will vary
depending on the actual chemistry received.
[0091] In preparing a feedstock, it is important first to measure
the actual density of each lot of both the metal powders and
binders. This is extremely important especially for the metal
powders in that each lot will be different based on the actual
chemistry of that grade of powder. For example, 316L is comprised
of several elements, such as Fe, Cr, Ni, Cu, Mo, P, Si, S and C. In
order to be rightfully called a 316L, each of these elements must
meet a minimum and maximum percentage weight requirement as called
out in the relevant specification. Tables I-IV below provide other
examples of the elemental compositions of some of the metal
powders, feed stocks, metals, alloys and compositions of the
present invention. Hence the variation in the chemistry within the
specification results in a significant density variation within the
acceptable composition range. Depending on the lot received from
the powder producer, the density will vary depending on the actual
chemistry received.
TABLE-US-00001 TABLE I Material Designation Chemical Composition, %
- Low-Alloy Steels Code Fe Ni Mo C Si (max) MIM-2200.sup.(1) Bal.
1.5-2.5 0.5 max 0.1 max 1.0 MIM-2700 Bal. 6.5-8.5 0.5 max 0.1 max
1.0 MIM-4605.sup.(2) Bal. 1.5-2.5 0.2-0.5 0.4-0.6 1.0
TABLE-US-00002 TABLE II Material Designation Chemical Composition,
% - Stainless Steels Code Fe Ni Cr Mo C Cu Nb + Ta Mn (max) Si
(max) MIM-316L Bal. 10-14 16-18 2-3 0.03 max -- -- 2.0 1.0 MIM-420
Bal. -- 12-14 -- 0.15-0.4 -- -- 1.0 1.0 MIM-430L Bal. -- 16-18 --
0.05 max -- -- 1.0 1.0 MIM-17-4 PH Bal. 3-5 15.5-17.5 -- 0.07 max
3-5 0.15-0.45 1.0 1.0
TABLE-US-00003 TABLE III Material Designation Chemical Composition,
% - Soft-Magnetic Alloys Code Fe Ni Cr Co Si C (max) Mn V MIM-2200
Bal. 1.5-2.5 -- -- 1.0 max 0.1 -- -- MIM-Fe-3%Si Bal. -- -- --
2.5-3.5 0.05 -- -- MIM-Fe50%Ni Bal. 49-51 -- -- 1.0 max 0.05 -- --
MIM-Fe50%Co Bal. -- -- 48-50 1.0 max 0.05 -- 2.5 max MIM-430L Bal.
-- 16-18 -- 1.0 max 0.05 1.0 max --
TABLE-US-00004 TABLE IV Nominal Chemical Composition, % -
Controlled-Expansion Alloys Material Mn Si C Al Mg Zr Ti Cu Cr Mo
Designation Fe Ni Co max max max max max max max max max max
MIM-F15 Bal. 29 17 0.50 0.20 0.04 0.10 0.10 0.10 0.10 0.20 0.20
0.20
[0092] In addition to the specific compositions listed herein, the
skill artisan recognizes the elemental composition of common
commercial designations used by feedstock manufacturers and
processors, e.g., C-0000 Copper and Copper Alloys; CFTG-3806-K
Diluted Bronze Bearings; CNZ-1818 Copper and Copper Alloys;
CNZP-1816 Copper and Copper Alloys; CT-1000 Copper and Copper
Alloys; CT-1000-K Bronze Bearings; CTG-1001-K Bronze Bearings;
CTG-1004-K Bronze Bearings; CZ-1000 Copper and Copper Alloys;
CZ-2000 Copper and Copper Alloys; CZ-3000 Copper and Copper Alloys;
CZP-1002 Copper and Copper Alloys; CZP-2002 Copper and Copper
Alloys; CZP-3002 Copper and Copper Alloys; F-0000 Iron and Carbon
Steel; F-0000-K Iron and Iron-Carbon Bearings; F-0005 Iron and
Carbon Steel; F-0005-K Iron and Iron-Carbon Bearings; F-0008 Iron
and Carbon Steel; F-0008-K Iron and Iron-Carbon Bearings; FC-0200
Iron-Copper and Copper Steel; FC-0200-K Iron-Copper Bearings;
FC-0205 Iron-Copper and Copper Steel; FC-0205-K Iron-Copper-Carbon
Bearings; FC-0208 Iron-Copper and Copper Steel; FC-0208-K
Iron-Copper-Carbon Bearings; FC-0505 Iron-Copper and Copper Steel;
FC-0508 Iron-Copper and Copper Steel; FC-0508-K Iron-Copper-Carbon
Bearings; FC-0808 Iron-Copper and Copper Steel; FC-1000 Iron-Copper
and Copper Steel; FC-1000-K Iron-Copper Bearings; FC-2000-K
Iron-Copper Bearings; FC-2008-K Iron-Copper-Carbon Bearings;
FCTG-3604-K Diluted Bronze Bearings; FD-0200 Diffusion-Alloyed
Steel; FD-0205 Diffusion-Alloyed Steel; FD-0208 Diffusion-Alloyed
Steel; FD-0400 Diffusion-Alloyed Steel; FD-0405 Diffusion-Alloyed
Steel; FD-0408 Diffusion-Alloyed Steel; FF-0000 Soft-Magnetic
Alloys; FG-0303-K Iron-Graphite Bearings; FG-0308-K Iron-Graphite
Bearings; FL-4005 Prealloyed Steel; FL-4205 Prealloyed Steel;
FL-4400 Prealloyed Steel; FL-4405 Prealloyed Steel; FL-4605
Prealloyed Steel; FL-4805 Prealloyed Steel; FL-48105 Prealloyed
Steel; FL-4905 Prealloyed Steel; FL-5208 Prealloyed Steel; FL-5305
Prealloyed Steel; FLC-4608 Sinter-Hardened Steel; FLC-4805
Sinter-Hardened Steel; FLC-48108 Sinter-Hardened Steel; FLC-4908
Sinter-Hardened Steel; FLC2-4808 Sinter-Hardened Steel; FLDN2-4908
Diffusion-Alloyed Steel; FLDN4C2-4905 Diffusion-Alloyed Steel;
FLN-4205 Hybrid Low-Alloy Steel; FLN-48108 Sinter-Hardened Steel;
FLN2-4400 Hybrid Low-Alloy Steel; FLN2-4405 Hybrid Low-Alloy Steel;
FLN2-4408 Sinter-Hardened Steel; FLN2C-4005 Hybrid Low-Alloy Steel;
FLN4-4400 Hybrid Low-Alloy Steel; FLN4-4405 Hybrid Low-Alloy Steel;
FLN4-4408 Sinter Hardened Steel; FLN4C-4005 Hybrid Low-Alloy Steel;
FLN6-4405 Hybrid Low-Alloy Steel; FLN6-4408 Sinter-Hardened Steel;
FLNC-4405 Hybrid Low-Alloy Steel; FLNC-4408 Sinter-Hardened Steel;
FN-0200 Iron-Nickel and Nickel Steel; FN-0205 Iron-Nickel and
Nickel Steel; FN-0208 Iron-Nickel and Nickel Steel; FN-0405
Iron-Nickel and Nickel Steel; FN-0408 Iron-Nickel and Nickel Steel;
FN-5000 Soft-Magnetic Alloys; FS-0300 Soft-Magnetic Alloys; FX-1000
Copper-Infiltrated Iron and Steel; FX-1005 Copper-Infiltrated Iron
and Steel; FX-1008 Copper-Infiltrated Iron and Steel; FX-2000
Copper-Infiltrated Iron and Steel; FX-2005 Copper-Infiltrated Iron
and Steel; FX-2008 Copper-Infiltrated Iron and Steel; FY-4500
Soft-Magnetic Alloys; FY-8000 Soft-Magnetic Alloys; P/F-1020 Carbon
Steel PF; P/F-1040 Carbon Steel PF; P/F-1060 Carbon Steel PF;
P/F-10C40 Copper Steel PF; P/F-10050 Copper Steel PF; P/F-10060
Copper Steel PF; P/F-1140 Carbon Steel PF; P/F-1160 Carbon Steel
PF; P/F-11C40 Copper Steel PF; P/F-11050 Copper Steel PF; P/F-11060
Copper Steel PF; P/F-4220 Low-Alloy P/F-42XX Steel PF; P/F-4240
Low-Alloy P/F-42XX Steel PF; P/F-4260 Low-Alloy P/F-42XX Steel PF;
P/F-4620 Low-Alloy P/F-46XX Steel PF; P/F-4640 Low-Alloy P/F-46XX
Steel PF; P/F-4660 Low-Alloy P/F-46XX Steel PF; P/F-4680 Low-Alloy
P/F-46XX Steel PF; SS-303L Stainless Steel--300 Series Alloy;
SS-303N1 Stainless Steel--300 Series Alloy; SS-303N2 Stainless
Steel--300 Series Alloy; SS-304H Stainless Steel--300 Series Alloy;
SS-304L Stainless Steel--300 Series Alloy; SS-304N1 Stainless
Steel--300 Series Alloy; SS-304N2 Stainless Steel--300 Series
Alloy; SS-316H Stainless Steel--300 Series Alloy; SS-316L Stainless
Steel--300 Series Alloy; SS-316N1 Stainless Steel--300 Series
Alloy; SS-316N2 Stainless Steel--300 Series Alloy; SS-409L
Stainless Steel--400 Series Alloy; SS-409LE Stainless Steel--400
Series Alloy; SS-410 Stainless Steel--400 Series Alloy; SS-410L
Stainless Steel--400 Series Alloy; SS-430L Stainless Steel--400
Series Alloy; SS-430N2 Stainless Steel--400 Series Alloy; SS-434L
Stainless Steel--400 Series Alloy; SS-434LCb Stainless Steel--400
Series Alloy; and SS-434N2 Stainless Steel--400 Series Alloy.
[0093] Both mold design factors such as runner and gate size, gate
placement, venting and molding parameters set on the molding
machine affect the molded part. A helium Pycnometer can determine
if there are voids trapped inside the parts. During molding, you
have a tool that can be used to measure the percent of theoretical
density achieved on the "Green" or molded part. By crushing the
measured "green" molded part back to powder, you can now confirm
the percent of air (or voids) trapped in the molded part. To
measure this, the density of the molded part should be measured in
the helium Pycnometer and compared to the theoretical density of
the feedstock. Then, take the same molded part that was used in the
density test and crush it back to powder. If this granulate shows a
density of more than 100% of that of the feedstock, then some of
the primary binders have been lost during the molding process. The
molding process needs to be corrected because using this process
with a degraded feedstock will result in a larger shrinkage and
result in a part smaller than that desired. It is vital to be sure
that your molded parts are completely filled before continuing the
manufacturing process for debinding and sintering. The helium
Pycnometer provides this assurance. Primary debinding properly
debound parts are extremely important to establish the correct
sintering profile. The primary binder must be completely removed
before attempting to start to remove the secondary binder as the
secondary binder will travel through the pores created by the
extraction of the primary binder. Primary debinding techniques
depend on the feedstock type used to make the parts. However the
feedstock supplier knows the amount of primary binders that have
been added and should be removed before proceeding to the next
process step. The feedstock supplier provides a minimum "brown
density" that must be achieved before the parts can be moved into a
furnace for final debinding and sintering. This minimum brown
density will take into account that a small amount of the primary
binder remnant may be present and could be removed by a suitable
hold during secondary debinding and sintering. The sintering
profile should be adjusted to remove the remaining small percent of
primary binder before the removal of the secondary binder. Most
external feedstock manufacturers provide only a weight loss percent
that should be obtained to define suitable debinding. Solvent
debound parts must be thoroughly dried, before the helium
Pycnometer is used to determine the "brown" density so that the
remnant solvent in the part does not affect the measured density
value. When the feedstock manufacturer gives you the theoretical
density of the "brown" or debound part, can validate the percent of
debinding that has been achieved. Most MIM operations today perform
the secondary debinding and sintering in the same operation. Every
MIM molder has gates and runners left over from molding their
parts. So, you will be able to now re-use your gates and runners
with confidence that they will shrink correctly after sintering. If
the feedstock producers have given you the actual and theoretical
densities of their feedstock, you can easily measure the densities
of the gates and runners and compare the results to the values
supplied. Once the regrind densities are higher than that required
to maintain the part dimensions, the regrinds are no longer
reusable.
[0094] Feedstock in accordance with the present invention may be
prepared by blending the powdered metal with the binder and heating
the blend to form a slurry. Uniform dispersion of the powdered
metal in the slurry may be achieved by employing high shear mixing.
The slurry may then be cooled to ambient temperature and then
granulated to provide the feedstock for the metal injection
molding.
[0095] One embodiment of the powdered metal may include a
composition where Ni may be 2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.5,
3.75, 4.0, 4.25, 4.50, 4.75, 5.0, 5.25, 5.5, 5.75, 6.0, 6.25, 6.50,
6.75, 7.0, 7.25, 7.5, 7.75, 8.0, 8.25, 8.50, 8.75, 9.0, 9.25, 9.5,
9.75, 10.0, 10.25, 10.50, 10.75, 11.0, 11.25, 11.5, 11.75, 12.0,
12.25, 12.50, 12.75, 13.0, 13.25, 13.5, 13.75, 14.0, 14.25, 14.50,
14.75, 15.0, 15.25, 15.5, 15.75, 16.0, 16.25, 16.50, 16.75, or
17.0%; Cr may be 9.0, 9.25, 9.5, 9.75, 10.0, 10.25, 10.50, 10.75,
11.0, 11.25, 11.5, 11.75, 12.0, 12.25, 12.50, 12.75, 13.0, 13.25,
13.5, 13.75, 14.0, 14.25, 14.50, 14.75, 15.0, 15.25, 15.5, 15.75,
16.0, 16.25, 16.50, 16.75, 17.0, 17.25, 17.5, 17.75, 18.0, 18.25,
18.50, 18.75, 19.0, 19.25, 19.5, 19.75, or 20.0%; Mo may be 0.00,
0.025, 0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250,
0.275, 0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50,
0.525, 0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750,
0.775, 0.80, 0.825, 0.850, 0.875, 0.90, 0.925, 0.950, 1.0, 1.25,
1.5, 1.75, 2.0, 2.25, 2.50, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25,
4.50, 4.75, 5.0, 5.25, 5.5, 5.75, 6.0, 6.25, 6.50, 6.75, or 7.0%; C
may be 0.00, 0.025, 0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20,
0.225, 0.250, 0.275, 0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450,
0.475, 0.50, 0.525, 0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70,
0.725, 0.750, 0.775, 0.80, 0.825, 0.850, 0.875, 0.90, 0.925, 0.950,
or 1.00%; Cu may be 0.00, 0.025, 0.050, 0.075, 0.10, 0.125, 0.150,
0.175, 0.20, 0.225, 0.250, 0.275, 0.30, 0.325, 0.350, 0.375, 0.40,
0.425, 0.450, 0.475, 0.50, 0.525, 0.550, 0.575, 0.60, 0.625, 0.650,
0.675, 0.70, 0.725, 0.750, 0.775, 0.80, 0.825, 0.850, 0.875, 0.90,
0.925, 0.950, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, 2.50, 2.75, 3.0,
3.25, 3.5, 3.75, 4.0, 4.25, 4.50, 4.75, 5.0, 5.25, 5.5, 5.75, 6.0,
6.25, 6.50, 6.75, 7.0, 7.25, 7.5, 7.75, or 8.0%; Nb+Ta may be 0.00,
0.025, 0.050, 0.075, 0.10, 0.125, 0.150, 0.175, 0.20, 0.225, 0.250,
0.275, 0.30, 0.325, 0.350, 0.375, 0.40, 0.425, 0.450, 0.475, 0.50,
0.525, 0.550, 0.575, 0.60, 0.625, 0.650, 0.675, 0.70, 0.725, 0.750,
0.775, or 0.80%; Mn may be 0.00, 0.025, 0.050, 0.075, 0.10, 0.125,
0.150, 0.175, 0.20, 0.225, 0.250, 0.275, 0.30, 0.325, 0.350, 0.375,
0.40, 0.425, 0.450, 0.475, 0.50, 0.525, 0.550, 0.575, 0.60, 0.625,
0.650, 0.675, 0.70, 0.725, 0.750, 0.775, 0.80, 0.825, 0.850, 0.875,
0.90, 0.925, 0.950, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, 2.50, 2.75,
3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50, 4.75, 5.0, 5.25, 5.5, 5.75,
or 6.0%; Si may be 0.00, 0.025, 0.050, 0.075, 0.10, 0.125, 0.150,
0.175, 0.20, 0.225, 0.250, 0.275, 0.30, 0.325, 0.350, 0.375, 0.40,
0.425, 0.450, 0.475, 0.50, 0.525, 0.550, 0.575, 0.60, 0.625, 0.650,
0.675, 0.70, 0.725, 0.750, 0.775, 0.80, 0.825, 0.850, 0.875, 0.90,
0.925, 0.950, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, 2.50, 2.75, 3.0,
3.25, 3.5, 3.75, or 4.0%; and the balance Fe. For example, one
embodiment of the powdered metal may include any amount in the
range of 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5%
Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe. One embodiment of
the powdered metal may include any amount in the range of 2-6% Ni;
13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn;
0-3.0% Si and the balance Fe. One embodiment of the powdered metal
may include any amount in the range of 3-5% Ni; 15.5-17.5% Cr;
0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and
the balance Fe. One embodiment of the powdered metal may include
any amount in the range of 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03%
C; 0-2% Mn; 0-1% Si and the balance Fe. One embodiment of the
powdered metal may include any amount in the range of 12-14% Cr;
0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe. One embodiment of
the powdered metal may include any amount in the range of 16-18%
Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe.
[0096] Titanium alloys that may be used in this invention include
any alloy or modified alloy known to the skilled artisan including
titanium grades 5-38 and more specifically titanium grades 5, 9,
18, 19, 20, 21, 23, 24, 25, 28, 29, 35, 36 or 38. Grades 5, 23, 24,
25, 29, 35, or 36 annealed or aged; Grades 9, 18, 28, or 38
cold-worked and stress-relieved or annealed; Grades 9, 18, 23, 28,
or 29 transformed-beta condition; and Grades 19, 20, or 21
solution-treated or solution-treated and aged. Grade 5, also known
as Ti6Al4V, Ti-6Al-4V or Ti 6-4, is the most commonly used alloy.
It has a chemical composition of 6% aluminum, 4% vanadium, 0.25%
(maximum) iron, 0.2% (maximum) oxygen, and the remainder titanium.
It is significantly stronger than commercially pure titanium while
having the same stiffness and thermal properties (excluding thermal
conductivity, which is about 60% lower in Grade 5 Ti than in CP
Ti); Grade 6 contains 5% aluminium and 2.5% tin. It is also known
as Ti-5Al-2.5Sn. This alloy has good weldability, stability and
strength at elevated temperatures; Grade 7 and 7H contains 0.12 to
0.25% palladium. This grade is similar to Grade 2. The small
quantity of palladium added gives it enhanced crevice corrosion
resistance at low temperatures and high pH; Grade 9 contains 3.0%
aluminium and 2.5% vanadium. This grade is a compromise between the
ease of welding and manufacturing of the "pure" grades and the high
strength of Grade 5; Grade 11 contains 0.12 to 0.25% palladium;
Grade 12 contains 0.3% molybdenum and 0.8% nickel; Grades 13, 14,
and 15 all contain 0.5% nickel and 0.05% ruthenium; Grade 16
contains 0.04 to 0.08% palladium; Grade 16H contains 0.04 to 0.08%
palladium; Grade 17 contains 0.04 to 0.08% palladium; Grade 18
contains 3% aluminum, 2.5% vanadium and 0.04 to 0.08% palladium;
Grade 19 contains 3% aluminum, 8% vanadium, 6% chromium, 4%
zirconium, and 4% molybdenum; Grade 20 contains 3% aluminum, 8%
vanadium, 6% chromium, 4% zirconium, 4% molybdenum and 0.04% to
0.08% palladium; Grade 21 contains 15% molybdenum, 3% aluminum,
2.7% niobium, and 0.25% silicon; Grade 23 contains 6% aluminum, 4%
vanadium, 0.13% (maximum) Oxygen; Grade 24 contains 6% aluminum, 4%
vanadium and 0.04% to 0.08% palladium. Grade 25 contains 6%
aluminum, 4% vanadium and 0.3% to 0.8% nickel and 0.04% to 0.08%
palladium; Grades 26, 26H, and 27 all contain 0.08 to 0.14%
ruthenium; Grade 28 contains 3% aluminum, 2.5% vanadium and 0.08 to
0.14% ruthenium; Grade 29 contains 6% aluminum, 4% vanadium and
0.08 to 0.14% ruthenium; Grades 30 and 31 contain 0.3% cobalt and
0.05% palladium; Grade 32 contains 5% aluminum, 1% tin, 1%
zirconium, 1% vanadium, and 0.8% molybdenum; Grades 33 and 34
contain 0.4% nickel, 0.015% palladium, 0.025% ruthenium, and 0.15%
chromium; Grade 35 contains 4.5% aluminum, 2% molybdenum, 1.6%
vanadium, 0.5% iron, and 0.3% silicon; Grade 36 contains 45%
niobium; Grade 37 contains 1.5% aluminum; and Grade 38 contains 4%
aluminum, 2.5% vanadium, and 1.5% iron. Its mechanical properties
are very similar to Grade 5, but has good cold workability similar
to grade 9. One embodiment includes a Ti6Al4V composition. One
embodiment includes a composition having 3-12% aluminum, 2-8%
vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder
titanium. More specifically, about 6% aluminum, about 4% vanadium,
about 0.25% iron, about 0.2% oxygen, and the remainder titanium.
For example, one Ti composition may include 10 to 35% Cr, 0.05 to
15% Al, 0.05 to 2% Ti, 0.05 to 2% Y2O5, with the balance being
either Fe, Ni or Co, or an alloy consisting of 20.+-.1.0% Cr,
4.5.+-.0.5% Al, 0.5.+-.0.1% Y2O5 or ThO2, with the balance being
Fe. For example, one Ti composition may include 15.0-23.0% Cr,
0.5-2.0% Si, 0.0-4.0% Mo, 0.0-1.2% Nb, 0.0-3.0% Fe, 0.0-0.5% Ti,
0.0-0.5% Al, 0.0-0.3% Mn, 0.0-0.1% Zr, 0.0-0.035% Ce, 0.005-0.025%
Mg, 0.0005-0.005% B, 0.005-0.3% C, 0.0-20.0% Co, balance Ni. Sample
Ti-based feedstock component includes 0-45% metal powder; 15-40%
binder; 0-10% Polymer (e.g., thermoplastics and thermosets);
surfactant 0-3%; lubricant 0-3%; sintering aid 0-1%. Another sample
Ti-based feedstock component includes about 62% TiH2 powder as a
metal powder; about 29% naphthalene as a binder; about 2.1-2.3%
polymer (e.g., EVA/epoxy); about 2.3% SURFONIC N-100 as a
Surfactant; lubricant is 1.5% stearic acid as a; about 0.4% silver
as a sintering Aid. Examples of metal compounds include metal
hydrides, such as TiH2, and intermetallics, such as TiAl and TiAl3.
A specific instance of an alloy includes Ti-6Al,4V, among others.
In another embodiment, the metal powder comprises at least
approximately 45% of the volume of the feedstock, while in still
another, it comprises between approximately 54.6% and 70.0%. In
addition, Ti--Al alloys may consists essentially of 32-38% of Al
and the balance of Ti and contains 0.005-0.20% of B, and the alloy
which essentially consists of the above quantities of Al and Ti and
contains, in addition to the above quantity of B, up to 0.2% of C,
up to 0.3% of 0 and/or up to 0.3% of N (provided that 0+N add up to
0.4%) and c) 0.05-3.0% of Ni and/or 0.05-3.0% of Si, and the
balance of Ti.
[0097] FIGS. 15A and 15B depict a view of the substantially
cylindrical open-ended polymeric bullet-end having a shoulder
forming chamber neck and a bullet. FIGS. 15A and 15B depict show
the substantially cylindrical open-ended polymeric bullet-end 18
has a shoulder 24 forming chamber neck 26 and a bullet (not shown).
One embodiment includes modifications to strengthen the neck of the
mouth 60 and to the internal base area 62 to reduce nose tearing
and lodging in the chamber. The substantially cylindrical
open-ended polymeric bullet-end 18 illustrates a lock 58 (e.g.,
0.030.times.0.003) and added a step to allow for the lock 58 to
flex out during firing. The polymer was added to the external area
to strengthen the neck of the mouth 60 and to the internal base
area 62. The interference of the bullet to the neck was increased
by adding the polymer to the inside of the neck 64 and the exit
lock modified by adding an angle to the rim 66.
[0098] FIG. 16 depicts an elevation view of a bullet-end component
of the polymeric cartridge casing. A cartridge (not shown) suitable
for use with high velocity rifles may be manufactured as a modular
component system with a middle body component (not shown) with one
end being connected to a bullet-end component 18 that is connected
to a bullet (not shown) inserted therein and the other end being
connected to a substantially cylindrical insert (not shown). As the
cartridge (not shown) is made as a modular component system it must
be assembled and fused together, e.g., the substantially
cylindrical insert (not shown) must be attached to the middle body
component (not shown) and the bullet-end component 18 must also be
attached to the middle body component (not shown). In addition, the
bullet (not shown) must be attached to the bullet-end component 18
at the forward end opening 16. The bullet-end component 18 has a
shoulder 24 forming chamber neck 26 and a forward end opening 16 at
one end to receive a bullet (not shown) and a powder chamber
coupling 68 at the other that mates to the powder chamber (not
shown). The forward end opening 16 may include a textured surface
70 that extends into the inner neck 64 to enhance the sealing of
the bullet (not shown) and the bullet-end component 18. The
textured surface 70 may be in the form of groves, slots, channels,
scratches or any other texture to increase the surface area to
enhance bonding of the bullet (not shown) and the bullet-end
component 18. For example, the forward end opening 16 may include a
textured surface 70 of channels that extend into the inner neck 64
to enhance the sealing of the bullet (not shown) and the bullet-end
component 18. During assembly the textured surface 70 provides
additional surface area for the adhesive to interact with and thus
secure the seal between the bullet (not shown) and the forward end
opening 16.
[0099] FIG. 17 depicts a side, cross-sectional view of a bullet-end
component of the polymeric cartridge casing. A cartridge (not
shown) suitable for use with high velocity rifles may be
manufactured as a modular component system with a middle body
component (not shown) with one end being connected to a bullet-end
component 18 that is connected to a bullet (not shown) inserted
therein and the other end being connected to a substantially
cylindrical insert (not shown). The cartridge (not shown) is made
as a modular component system it must be assembled and fused
together, e.g., the substantially cylindrical insert (not shown)
must be attached to the middle body component (not shown) and the
bullet-end component 18 must also be attached to the middle body
component (not shown). In addition, the bullet (not shown) must be
attached to the bullet-end component 18 at the forward end opening
16. The bullet-end component 18 has a shoulder 24 forming chamber
neck 26 and a forward end opening 16 at one end to receive a bullet
(not shown) and a powder chamber coupling 68 at the other that
mates to the powder chamber (not shown). The forward end opening 16
may include a textured surface 70 that extends into the inner neck
64 to enhance the sealing of the bullet (not shown) and the
bullet-end component 18. The textured surface 70 may be in the form
of groves, slots, channels, scratches or any other texture to
increase the surface area to enhance bonding of the bullet (not
shown) and the bullet-end component 18. For example, the forward
end opening 16 may include a textured surface 70 of channels or
grooves that extend into the inner neck 64 to enhance the sealing
of the bullet (not shown) and the bullet-end component 18. During
assembly the textured surface 70 provides additional surface area
for the adhesive to interact with and thus secure the seal between
the bullet (not shown) and the forward end opening 16. For example
the textured surface 70 may be grooves that extend into the inner
neck 64 so that an adhesive when applied to the bullet can wick
into the grooves and into the inner neck 64 to provide a contact
area on the bullet and the inner neck 64 for the adhesive. The
adhesive can then be cured (e.g., UV light) and sealed. The
textured surface 70 may be in any form that allows wicking and/or
the increasing of the surface area, e.g., hatching, grooves,
scratches, roughness, etc.
[0100] The description of the preferred embodiments should be taken
as illustrating, rather than as limiting, the present invention as
defined by the claims. As will be readily appreciated, numerous
combinations of the features set forth above can be utilized
without departing from the present invention as set forth in the
claims. Such variations are not regarded as a departure from the
spirit and scope of the invention, and all such modifications are
intended to be included within the scope of the following
claims.
[0101] It is contemplated that any embodiment discussed in this
specification can be implemented with respect to any method, kit,
reagent, or composition of the invention, and vice versa.
Furthermore, compositions of the invention can be used to achieve
methods of the invention.
[0102] It will be understood that particular embodiments described
herein are shown by way of illustration and not as limitations of
the invention. The principal features of this invention can be
employed in various embodiments without departing from the scope of
the invention. Those skilled in the art will recognize, or be able
to ascertain using no more than routine experimentation, numerous
equivalents to the specific procedures described herein. Such
equivalents are considered to be within the scope of this invention
and are covered by the claims.
[0103] All publications and patent applications mentioned in the
specification are indicative of the level of skill of those skilled
in the art to which this invention pertains. All publications and
patent applications are herein incorporated by reference to the
same extent as if each individual publication or patent application
was specifically and individually indicated to be incorporated by
reference.
[0104] The use of the word "a" or "an" when used in conjunction
with the term "comprising" in the claims and/or the specification
may mean "one," but it is also consistent with the meaning of "one
or more," "at least one," and "one or more than one." The use of
the term "or" in the claims is used to mean "and/or" unless
explicitly indicated to refer to alternatives only or the
alternatives are mutually exclusive, although the disclosure
supports a definition that refers to only alternatives and
"and/or." Throughout this application, the term "about" is used to
indicate that a value includes the inherent variation of error for
the device, the method being employed to determine the value, or
the variation that exists among the study subjects.
[0105] As used in this specification and claim(s), the words
"comprising" (and any form of comprising, such as "comprise" and
"comprises"), "having" (and any form of having, such as "have" and
"has"), "including" (and any form of including, such as "includes"
and "include") or "containing" (and any form of containing, such as
"contains" and "contain") are inclusive or open-ended and do not
exclude additional, unrecited elements or method steps.
[0106] The term "or combinations thereof" as used herein refers to
all permutations and combinations of the listed items preceding the
term. For example, "A, B, C, or combinations thereof" is intended
to include at least one of: A, B, C, AB, AC, BC, or ABC, and if
order is important in a particular context, also BA, CA, CB, CBA,
BCA, ACB, BAC, or CAB. Continuing with this example, expressly
included are combinations that contain repeats of one or more item
or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so
forth. The skilled artisan will understand that typically there is
no limit on the number of items or terms in any combination, unless
otherwise apparent from the context.
[0107] All of the compositions and/or methods disclosed and claimed
herein can be made and executed without undue experimentation in
light of the present disclosure. While the compositions and methods
of this invention have been described in terms of preferred
embodiments, it will be apparent to those of skill in the art that
variations may be applied to the compositions and/or methods and in
the steps or in the sequence of steps of the method described
herein without departing from the concept, spirit and scope of the
invention. All such similar substitutes and modifications apparent
to those skilled in the art are deemed to be within the spirit,
scope and concept of the invention as defined by the appended
claims.
* * * * *