U.S. patent application number 12/510017 was filed with the patent office on 2013-05-02 for reactive material enhanced projectiles, devices for generating reactive material enhanced projectiles and related methods.
The applicant listed for this patent is Frederick P. Stecher, Richard M. Truitt. Invention is credited to Frederick P. Stecher, Richard M. Truitt.
Application Number | 20130104765 12/510017 |
Document ID | / |
Family ID | 48171058 |
Filed Date | 2013-05-02 |
United States Patent
Application |
20130104765 |
Kind Code |
A1 |
Stecher; Frederick P. ; et
al. |
May 2, 2013 |
REACTIVE MATERIAL ENHANCED PROJECTILES, DEVICES FOR GENERATING
REACTIVE MATERIAL ENHANCED PROJECTILES AND RELATED METHODS
Abstract
A liner assembly for an explosively formed projectile device may
include a reactive material liner and a primary liner configured to
form into a projectile responsive to initiation of an explosive
material. The reactive material liner may be configured and
formulated to increase the velocity of the projectile after
formation thereof. An ordnance device for generating an explosively
formed projectile may include a case, an explosive material, and a
reactive material liner and a primary liner configured, in
combination, to form into a projectile. An explosively formed
projectile may include a deformed primary liner and a deformed
reactive material liner having an ignited portion increasing the
velocity of the projectile. Methods of explosively forming a
projectile may include explosively expelling a primary liner and a
secondary liner and increasing the velocity of the projectile by
combusting at least a portion of the secondary liner.
Inventors: |
Stecher; Frederick P.;
(Corcoran, MN) ; Truitt; Richard M.; (Champlin,
MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stecher; Frederick P.
Truitt; Richard M. |
Corcoran
Champlin |
MN
MN |
US
US |
|
|
Family ID: |
48171058 |
Appl. No.: |
12/510017 |
Filed: |
July 27, 2009 |
Current U.S.
Class: |
102/476 |
Current CPC
Class: |
F42B 3/08 20130101; F42B
12/10 20130101; F42B 1/032 20130101; F42B 1/028 20130101 |
Class at
Publication: |
102/476 |
International
Class: |
F42B 12/10 20060101
F42B012/10 |
Claims
1. A liner assembly for use with a device for forming an
explosively formed projectile, the liner assembly comprising: a
reactive material liner comprising a reactive material; a primary
liner configured to, upon initiation of an explosive material used
to form an explosively formed projectile, deform into an outer
portion of the projectile at least partially surrounding a portion
of the reactive material liner and wherein at least a portion of
the reactive material liner is configured and formulated to
increase a velocity of the projectile in excess of a velocity
generated by the explosive material material; and a control liner
comprising a control material, the control liner disposed on at
least a portion of the reactive material liner and wherein the
control liner is configured and formulated to, upon initiation of
the explosive material used to form the explosively formed
projectile, defoim into a posterior portion of the projectile and
to at least partially control a rate of reaction of an ignited
portion of the reactive material liner.
2. The liner assembly of claim 1, wherein the primary liner is
configured and formulated to, upon initiation of the explosive
material used to form the explosively formed projectile, deform
into a substantially elongated shaped outer portion of the
projectile.
3. The liner assembly of claim 2, wherein the reactive material
liner is configured and formulated to deform into a central portion
of the projectile.
4. The liner assembly of claim 1, wherein the primary liner is
disposed over at least a portion of the reactive material liner and
wherein the primary liner and the reactive material liner are each
formed to have a substantially curved shape.
5. The liner assembly of claim 1, wherein the primary liner
comprises copper material.
6. The liner assembly of claim 5, wherein the reactive material
liner comprises a metal material selected from at least one of
tungsten, zirconium, aluminum, and nickel.
7. The liner assembly of claim 6, wherein the reactive material
liner further comprises an oxidizer material selected from at least
one of potassium perchlorate, potassium nitrate, ammonium
perchlorate, and cupric oxide.
8. (canceled)
9. The liner assembly of claim 1, further comprising: a buffer
liner comprising a buffer material at least partially disposed on
the reactive material liner and configured to, upon initiation of
the explosive material used in the explosively formed projectile,
deform into a central portion of the projectile; and an additional
reactive material liner comprising an additional reactive material
disposed on at least a portion of the buffer liner and configured
and formulated to, upon initiation of the explosive material used
to form the explosively formed projectile, deform into the central
portion of the projectile and wherein the buffer liner is
configured to at least partially separate the reactive material
liner and the additional reactive material liner.
10. The liner assembly of claim 1, wherein at least a portion of
the reactive material liner is configured and foimulated to ignite
when the reactive material liner is deformed.
11. The liner assembly of claim 10, wherein the primary liner is
configured to deform into the outer portion of the projectile
exposing a portion of the reactive material liner at a posterior
end of the projectile.
12. The liner assembly of claim 11, wherein the reactive material
liner is configured and formulated to form a propulsive jet created
by the ignition of the reactive material liner to increase the
velocity of the projectile.
13. An ordnance device for generating an explosively formed
projectile comprising: a case; an explosive material at least
partially disposed within the case; a reactive material liner
comprising a reactive material at least partially disposed within
the case; and a primary liner at least partially disposed within
the case and abutting at least a portion of a surface of the
reactive material liner, the primary liner configured to deform
into an outer portion of a projectile at least partially
surrounding a portion of the reactive material liner responsive to
initiation of the explosive material, and wherein at least a
portion of the reactive material liner is configured and formulated
to increase a velocity of the projectile in excess of a velocity
generated by the explosive material after the projectile has been
expelled from the case.
14. The ordnance device of claim 13, wherein the explosive material
is configured and formulated to propel the projectile formed by the
reactive material liner and the primary liner from the case at a
first initial velocity and a portion of the reactive material liner
is configured and formulated to accelerate the projectile to a
second, increased velocity.
15. The ordnance device of claim 14, wherein the second, increased
velocity is at least 10% greater than the first initial
velocity.
16. The ordnance device of claim 13, wherein at least a portion of
the reactive material liner is configured and formulated to ignite
upon being explosively expelled from the case.
17. The ordnance device of claim 13, further comprising a control
liner comprising a control material, the control liner at least
partially disposed within the case and at least partially disposed
between the reactive material liner and the explosive material and
wherein the control liner is configured to deform into a posterior
portion of the projectile after being explosively expelled from the
case and to at least partially control a rate of reaction of a
portion of the reactive material liner.
18. An explosively formed projectile comprising: a deformed primary
liner substantially forming an outer portion of the projectile; and
a deformed reactive material liner at least partially disposed
within the deformed primary liner and wherein an ignited portion of
the deformed reactive material liner increases a velocity of the
projectile in excess of a velocity generated by an explosive
material used to form the projectile.
19. The explosively formed projectile of claim 18, wherein the
deformed reactive material liner forms a portion of a central
portion of the projectile.
20. The explosively formed projectile of claim 19, further
comprising a defoiiiied control liner forming a posterior portion
of the projectile and at least partially surrounding a portion of
the deformed reactive material liner, the deformed control liner at
least partially controlling a rate of reaction of the ignited
portion of the deformed reactive material liner.
21. The explosively formed projectile of claim 20, further
comprising: a deformed buffer liner forming at least a portion of
the central portion of the projectile; and an additional deformed
reactive material liner forming at least a portion of an anterior
portion of the projectile, wherein the deformed buffer liner at
least partially separates the deformed reactive material liner and
the additional deformed reactive material liner.
22. (Withdrawn and Previously Presented) A method of explosively
forming a projectile with the liner assembly of claim 1, the method
comprising: explosively expelling the primary liner and the
reactive material liner from a case; deforming the primary liner to
at least partially surround a portion of the reactive material
liner; and increasing a velocity of the projectile by combusting at
least a portion of the reactive material liner.
23. (Withdrawn and Previously Presented) The method of claim 22,
further comprising igniting a portion of the reactive material
liner as the reactive material liner is explosively expelled from
the case.
Description
TECHNICAL FIELD
[0001] Embodiments of the present invention relate generally to
explosively formed projectiles. More particularly, embodiments of
the present invention relate to explosively formed projectiles,
devices for generating explosively formed projectiles including
reactive materials and reactive material configurations suitable
for increasing the velocity of explosively formed projectiles.
BACKGROUND
[0002] Explosively formed projectiles ("EFP") (also known as
explosively formed penetrators, and explosively formed perforators)
are provided by so-called "shaped charges" which utilize explosive
energy to deform a liner disposed over a concave-shaped explosive
material into a coherent projectile while simultaneously
accelerating it to extremely high velocities. An EFP offers a
method of employing a kinetic energy projectile without the use of
a large gun. A conventional EFP device is comprised of a metallic
liner, a case, an explosive material, and an initiator. The case
may also contain a retaining ring to position and hold the
liner-explosive subassembly in place. EFP devices are normally
designed to produce a single massive, high velocity projectile that
has a high kinetic energy capable of penetrating solid objects,
such as, for example, a target in the form of an armored vehicle or
a subterranean formation. Upon detonation, the explosive material
creates enormous pressures that accelerate the liner while
simultaneously reshaping it into a projectile of a rod-like or
other desired shape. On impact with a target, the EFP delivers a
high mechanical power in an extremely focused manner, enabling
penetration of target materials which are impervious to
conventional explosives.
[0003] The liner of the EFP device is formed from a solid material
that is formed into a projectile responsive to detonation of the
explosive charge. The liner material is typically a high-density,
ductile material, such as a metal, a metal alloy, a ceramic, or a
glass. The metals commonly used in liners include iron, copper,
aluminum, molybdenum, depleted uranium, tungsten, and tantalum.
Depending on the mechanical strength characteristics of the target,
penetration by the liner may heavily damage or destroy the target
in the vicinity of impaction by the projectile formed from the
liner. However, if the target is an armored vehicle or other
heavily armored target, the liner may not cause the desired degree
of damage. The destructive capability of the EFP may be limited by
the geometry and weight of the projectile formed from the liner by
the EFP device and the velocity imparted to the projectile by the
detonation of the explosive material. Further, aerodynamic drag
will generally act to decrease the velocity of projectile as the
projectile travels toward the target.
[0004] In some applications, in order to improve the destructive
capability of the warhead, the liner may be provided with the
ability to produce secondary reactions that cause additional
damage. These secondary reactions commonly include incendiary
reactions. As disclosed in U.S. Pat. No. 4,807,795 to LaRocca et
al., pyrophoric metals are added to the liner to provide the
desired incendiary effects. In LaRocca et al., a double-layered
liner is disclosed, where a layer of dense metal provides the
penetration ability and a layer of light metal, such as aluminum or
magnesium, produces the incendiary effects.
[0005] While metals have been commonly used in liners, reactive
materials have also been used. Upon impact with a target, the
reactive material of the liner produces a high burst of energy.
Such reactive materials for use in penetrating warheads are
disclosed, for example, in U.S. Pat, No. 6,962,634, issued Nov. 8,
2005, entitled "Low Temperature, Extrudable, High Density Reactive
Materials" and assigned to the assignee of the present invention,
the entire disclosure of which patent is incorporated herein by
this reference.
BRIEF SUMMARY
[0006] In accordance with some embodiments of the present
invention, a liner assembly for an explosively formed projectile
device may include a reactive material liner comprising a reactive
material and a primary liner. The primary liner may be configured
to, upon initiation of an explosive material used to form an
explosively formed projectile, deform into an outer portion of the
projectile at least partially surrounding a portion of the reactive
material liner. At least a portion of the reactive material liner
may be configured and formulated to increase a velocity of the
projectile in excess of a velocity generated by the explosive
material.
[0007] In additional embodiments, the present invention includes an
ordnance device for generating an explosively formed projectile
including a case, an explosive material at least partially disposed
within the case, a reactive material liner comprising a reactive
material at least partially disposed within the case, and a primary
liner at least partially disposed within the case and abutting at
least a portion of a surface of the reactive material liner. The
primary liner may be configured to deform into an outer portion of
a projectile at least partially surrounding a portion of the
reactive material liner after being expelled from the case
responsive to initiation of the explosive material. At least a
portion of the reactive material liner may be configured and
formulated to increase a velocity of the projectile in excess of a
velocity generated by the explosive material.
[0008] In yet additional embodiments, the present invention
includes an explosively formed projectile including a deformed
primary liner substantially forming an outer portion of the
projectile and a deformed reactive material liner at least
partially disposed within the deformed primary liner. An ignited
portion of the deformed reactive material liner may increase a
velocity of the projectile in excess of a velocity generated by an
explosive material used to form the projectile.
[0009] In yet additional embodiments, the present invention
includes a method of configuring an explosively formed projectile
device including arranging an explosive material at least partially
within a case, arranging a reactive material liner at least
partially on the explosive material, and arranging a primary liner
at least partially on the reactive material liner. The method
further includes configuring the primary liner and the reactive
material liner to form a explosively formed projectile, configuring
and formulating a portion of the reactive material liner to ignite
when the reactive material liner is explosively expelled from the
case, and configuring the ignited portion of the reactive material
liner to increase the velocity of the explosively formed projectile
after the forming explosively formed projectile is explosively
expelled from the case.
[0010] In yet additional embodiments, the present invention
includes a method of explosively forming a projectile including
explosively expelling a primary liner and a secondary liner from a
case, deforming the primary liner to at least partially surround a
portion of the secondary liner, and increasing a velocity of the
projectile by combusting at least a portion of the secondary
liner.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] While the specification concludes with claims particularly
pointing out and distinctly claiming that which is regarded as the
present invention, the advantages of this invention may be more
readily ascertained from the following description of embodiments
of the invention when read in conjunction with the accompanying
drawings in which:
[0012] FIGS. 1A and 1B are, respectively, longitudinal
cross-sectional views of a device including a reactive material
liner in accordance with an embodiment of the present invention for
generating an explosively formed projectile and an explosively
formed projectile resulting from initiation of the device;
[0013] FIGS. 2A and 2B are, respectively, longitudinal
cross-sectional views of an another embodiment of a device
including a reactive material liner and a control liner for
generating an explosively formed projectile and an explosively
formed projectile resulting from initiation of the device;
[0014] FIGS. 3A and 3B are, respectively, longitudinal
cross-sectional views of an another embodiment of a device
including a reactive material liner, a buffer liner, an additional
reactive material liner, and a control liner for generating an
explosively formed projectile and an explosively formed projectile
resulting from initiation of the device;
[0015] FIGS. 4A and 4B are, respectively, longitudinal
cross-sectional views of a yet another embodiment of a device
including a reactive material liner for generating an explosively
formed projectile and an explosively formed projectile resulting
from initiation of the device.
DETAILED DESCRIPTION
[0016] The illustrations presented herein are not meant to be
actual views of any particular material, apparatus, system, or
method, but are merely idealized representations which are employed
to describe embodiments of the present invention. Additionally,
elements common between figures may retain the same numerical
designation.
[0017] An embodiment of an ordnance device such as a device for
generating an EFP, which may be termed an "EFP device" 100 is
illustrated in FIG. 1A. The EFP device 100 may include a case 102,
an initiator 104, an explosive material 106, and a first liner such
as a primary liner 108. In some embodiments, the case 102 may be
formed in a shape such as a generally cylindrical tube. Further,
the case 102 may be comprised of a material such as steel, a
plastic, or a composite material. It is noted that while the case
shown in FIG. 1A is formed as a generally cylindrical tube; the
case 102 may be formed in other suitable shapes in order to produce
the desired shape of the projectile. For example, the case 102 may
be formed in a shape such as an elongated rectangular, square,
oval, or any other desired shape suitable to produce an explosively
formed projectile. As shown in FIG. 1A, the case 102 may have a
substantially flat rear surface and walls extending perpendicular
to the rear surface. For example, the case 102 may have a
substantially hollow cylindrical shape and may have an inside
diameter of approximately 1.3 to 16 centimeters (approximately 0.5
to 6 inches). In some embodiments, the case 102 may not have a
substantially flat rear surface and may have a non-planar shape
such as a concave, convex, or conical shape.
[0018] At least a portion of the case 102 may be filled with the
explosive material 106. The explosive material 106 may be formed
within the interior of the case 102 and may comprise an explosive
material 106 such as polymer-bonded explosives ("PBX"), LX-14, C-4,
OCTOL, trinitrotoluene ("TNT"); cyclo-1,3,5-trimethylene-2,4,6
trinitramine ("RDX"); cyclotetramethylene tetranitramine ("HMX");
hexanitrohexaazaisowurtzitane ("CL 20"), C-4, combinations thereof,
or any other suitable explosive material. In some embodiments, the
explosive material 106 may also be formed to have a countersunk
recess in a forward surface of the explosive material 106 to
receive the placement of a liner or liners. As used herein, the
term "forward surface" is meant to describe the surface of the
material or liner that faces the open end of the case 102 from
which a forming projectile is expelled. The case 102 may also
include a detonator such as the initiator 104 located, for example,
at the rear surface of the case 102. The initiator 104 may comprise
any known detonation device sufficient to detonate the explosive
material 106 within the case 102 including, but not limited to,
explosives such as pentaerythritol tetranitrate ("PETN"), PBXN-5,
CH-6, blasting caps, and electronic detonators (e.g., exploding
foil initiators).
[0019] As shown in FIG. 1A, the EFP device 100 may include a second
or secondary liner such as a reactive material liner 110 that is,
for example, formed on the explosive material 106. Depending on the
material properties of the composition selected for the reactive
material liner 110, the reactive material liner 110 may be formed
in a predefined shape by a process such as machining, extrusion,
injection molding, etc. The reactive material liner 110 may be
formed to substantially fit the shape of the forward surface of the
explosive material 106.
[0020] In some embodiments, the reactive material liner 110 may
include reactive materials including, for example, at least one
fuel and, optionally, an oxidizer. In some embodiments, the
reactive material utilized in the reactive material liner 110 may
include two or more components selected from a fuel, an oxidizer,
and a class 1.1 explosive. Binders, polymers, plasticizers, and
matrix materials may also be incorporated with various embodiments
of the invention as part of the reactive materials or as support
structures for the reactive materials. In addition, the reactive
material may include an ignition initiator suitable for igniting or
initiating combustion of the reactive material.
[0021] Fuels that may be used to form reactive materials according
to embodiments of the invention may include, but are not limited
to, metals, fusible metal alloys, organic fuels, and mixtures
thereof. Suitable metals that may be used as fuels in reactive
materials include metals such as, for example, hafnium, tantalum,
nickel, zinc, tin, silicon, palladium, bismuth, iron, copper,
phosphorous, aluminum, tungsten, zirconium, magnesium, boron,
titanium, sulfur, magnalium, and mixtures thereof An organic fuel
that may be incorporated into the reactive materials may include,
but is not limited to, a mixture of phenolphthalein and hexamine
cobalt(III)nitrate (HACN). Fusible metal alloys may include an
alloy of a metal selected from the group of gallium, bismuth, lead,
tin, cadmium, indium, mercury, antimony, copper, gold, silver, and
zinc.
[0022] The reactive materials according to embodiments of the
invention may also include oxidizers mixed with one or more fuels
or with class 1.1 explosives. Oxidizers that may be used to form
reactive materials according to embodiments of the invention may
include, but are not limited to, inorganic oxidizers, sulfur,
fluoropolymers, and mixtures thereof For example, an oxidizer may
include ammonium perchlorate, potassium perchlorate, potassium
nitrate, strontium nitrate, basic copper nitrate, ammonium nitrate,
cupric oxide, tungsten oxides, silicon dioxide, manganese dioxide,
molybdenum trioxide, bismuth oxides, iron oxide, molybdenum
trioxide, hafnium oxide, zirconium oxide, polytetrafluoroethylene,
thermoplastic terpolymers of tetrafluoroethylene,
hexafluoropropylene, vinylidene fluoride (THV), copolymers of
vinylidenefluoride-hexafluoropropylene, and mixtures thereof.
[0023] The reactive material may, optionally, include a class 1.1,
detonable energetic material, such as a nitramine or a nitrocarbon.
The energetic material may include, but is not limited to,
trinitrotoluene ("TNT"); cyclo-1,3,5-trimethylene-2,4,6
trinitramine ("RDX"); cyclotetramethylene tetranitramine ("HMX");
hexanitrohexaazaisowurtzitane ("CL 20"); 4,10 dinitro 2,6,8,12
tetraoxa 4,10 diazatetracyclo [5.5.0.0 5,9.0 3,11] dodecane
("TEX"); 1,3,3 trinitroazetine ("TNAZ"); ammonium dinitramide
("ADN"); 2,4,6 trinitro 1,3,5 benzenetriamine ("TATB");
dinitrotoluene ("DNT"); dinitroanisole ("DNAN"); or combinations
thereof.
[0024] Reactive materials according to embodiments of the invention
may also include binder materials. The binder, if present, may be a
curable organic binder, a thermoplastic fluorinated binder, a
non-fluorinated organic binder, a fusible metal alloy, an epoxy
resin, silicone, nylon, or combinations thereof. The binder may be
a high-strength, inert material including, but not limited to,
polyurethane, epoxy, silicone, or a fluoropolymer. Alternatively,
the binder may be an energetic material, such as glycidyl azide
polymer ("GAP") polyol. The binder may enable the reactive material
to be pressed, cast, or extruded into a desired shape. The
thermoplastic fluorinated binder may include, but is not limited
to, polytetrafluoroethylene ("PTFE"); a thermoplastic terpolymer of
tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride
("THV"); perfluorosuccinyl polyether di-alcohol; a fluoroelastomer;
or combinations thereof
[0025] The reactive materials used according to embodiments of the
invention may, optionally, include ignition initiators which are
suitable for igniting the reactive materials after the reactive
material liner 110 has been explosively expelled from the case 102.
The ignition initiators may be formed or mixed with the reactive
materials or may be a distinct, separate material from the reactive
material. The ignition initiator may be optional because the
reactive material may ignite on launch due to external forces such
as an explosive shockwave formed by the detonation of the explosive
material 106 or the reactive material may ignite due to aerodynamic
heating of the reactive material in contact with air. Ignition
initiators according to embodiments of the invention include
materials that are capable of producing sufficient thermal activity
to ignite the reactive materials. For example, the ignition
initiators may include reactive powders, electrical wires, or
reactive foils. Ignition initiators incorporated with a reactive
material of particular embodiments of the invention may be
activated, releasing thermal energy which ignites the reactive
materials.
[0026] In other embodiments of the invention, an ignition initiator
is mixed or blended with a reactive material. For example, a
reactive powder suitable as an ignition initiator may be mixed with
components used to form a reactive material, such as with a fuel or
oxidizer. Examples of reactive powders suitable as ignition
initiators include a metal powder in combination with an oxidizer.
The metal powder may include, but is not limited to, zirconium,
aluminum, hafnium, titanium, nickel, iron, boron, silicon, tin,
zinc, tungsten, copper, or combinations thereof. The oxidizer may
be potassium perchlorate, potassium nitrate, bismuth oxide, hafnium
oxide, iron oxide, an alkali metal nitrate, a fluoropolymer, or
combinations thereof Each of the metal powder and the oxidizer may
have a small particle size, such as less than approximately 20
.mu.m. If faster rates of reactions or burn rates are desired, the
metal powder and the oxidizer may have a particle size on the order
of several nanometers.
[0027] Other reactive materials, binders, polymers, plasticizers,
and ignition initiators that may be incorporated with the reactive
materials according to embodiments of the invention may include
those materials disclosed in the following United States Patents
and Patent Applications, the disclosure of each of which is
incorporated herein by reference in its entirety: U.S. Pat. No.
6,593,410; U.S. Pat. No. 6,962,634; U.S. patent application Ser.
No. 11/079,925, entitled "Reactive Material Enhanced Projectiles
and Related Methods," filed Mar. 14, 2005; U.S. patent application
Ser. No. 11/538,763, entitled "Reactive Material Enhanced
Projectiles and Related Methods," filed Oct. 4, 2006; U.S. patent
application Ser. No. 11/512,058, entitled "Weapons and Weapon
Components Incorporating Reactive Materials and Related Methods,"
filed Aug. 29, 2006; U.S. patent application Ser. No. 11/620,205,
entitled "Reactive Compositions Including Metal" filed on Jan. 5,
2007; U.S. patent application Ser. No. 11/690,016, entitled
"Reactive Material Compositions, Shot Shells Including Reactive
Materials, and A Method Of Producing Same," filed Mar. 22, 2007;
U.S. patent application Ser. No. 11/697,005, entitled "Consumable
Reactive Material Fragments, Ordnance Incorporating Structures for
Producing the Same, and Methods of Creating the Same," filed Apr.
5, 2007; and U.S. patent application Ser. No. 12/127,627, entitled
"Reactive Material Enhanced Munition Compositions and Projectiles
Containing Same" filed on May 27, 2008.
[0028] Referring again to FIG. 1A, the EFP device may include a
primary liner 108 formed from one or more materials such as a
metal, a metal alloy, a ceramic, or a glass. The metal and metal
alloy materials may include materials such as iron, copper, steel,
aluminum, molybdenum, tungsten, tantalum, etc. Further, the primary
liner 108 may also be formed from reactive materials such as the
reactive materials previously described in reference to the
reactive material liner 110. Similar to the reactive material liner
110, the primary liner 108 may be formed in a predefined shape in
order to substantially fit the shape of an adjacent surface such as
the forward surface of the reactive material liner 110. It is noted
that while the embodiment shown in FIG. 1A details a primary liner
108 and a reactive material liner 110 having a substantially curved
shape (e.g., a concave shape, a conical shape, etc.), the primary
liner 108, the reactive material liner 110, and the explosive
material 106 may be formed in other shapes such as a disc shapes,
convex shapes, tapered shapes, cones, spheres, hemispheres,
cylinders, tubes, lines, L-beams, etc. As may be appreciated by one
of ordinary skill in the art, the shape of the case 102, explosive
material 106, and liner or liners (e.g., the primary liner 108 and
the reactive material liner 110 shown in FIG. 1A) may be utilized
to determine the shape of the projectile 101 (FIG. 1B) produced by
the EFP device 100. It is further noted, that the various liners
are described herein as being formed in layers on the explosive
material 106 to illustrate the different liners in the EFP device
100 and such a process is not meant as a limitation. It is
contemplated by the current invention that the liners may be formed
by processes such as, for example, forming the liners together in a
laminate structure which is then disposed on the explosive
material, forming the liners and the explosive material and then
disposing the liners and explosive material in the case, or
injection molding a liner or liners between other liners or the
explosive material.
[0029] In some embodiments, the thickness of the liners 108 and 110
may be utilized to determine the geometry and size and the
projectile 101 (FIG. 1B) produced by the EFP device 100. The
primary liner 108 may have a thickness, for example, measuring 0.75
to 2.00 mm (approximately 0.03 to 0.08 inches) and the reactive
material liner 110 may have a thickness, for example, measuring
1.25 to 3.80 mm (approximately 0.05 to 0.15 inches). In some
embodiments, the primary liner 108 and the reactive material liner
110 may have a substantially consistent thickness throughout the
liner. In other embodiments, the thickness of the liners 108 and
110 may vary throughout the liners and the liners 108 and 110 may
also contain protrusions and cavities through the liners in order
to produce the desired geometry of the explosively formed
projectile 101 upon expulsion of the forming projectile 101 from
the case 102.
[0030] In order to retain the explosive material 106 and the
primary liner 108 and the reactive material liner 110 at least
partially within the case 102, the explosive material 106, the
primary liner 108, and the reactive material liner 110 may be
mounted together physically, for example, by a retaining ring
disposed around and fixed to the open end of the case 102. In some
embodiments, the explosive material 106, the primary liner 108, and
the reactive material liner 110 may be held together by an
adhesive, by another mechanical attachment, or by a combination of
adhesive and mechanical attachments.
[0031] Referring now to FIGS. 1A and 1B, when the explosive
material 106 in the EFP device 100 is detonated, the primary liner
108 and the reactive material liner 110 form a projectile 101 that
has a high kinetic energy capable of penetrating solid objects,
such as a target. In order to expel the primary liner 108 and the
reactive material liner 110 from the case 102, the explosive
material 106 may be detonated by the initiator 104. A high pressure
(e.g., 100 to 400 kilobars) detonation shockwave is generated by
the rapidly combusting explosive material. The high pressure
explosive gases behind the detonation shockwave impart energy and
projectile formation forces to the primary liner 108 and the
reactive material liner 110. The shockwave created by detonation of
the explosive material 106 may propagate radially or linearly
through the EFP device 100 from the initiator 104 toward the open
end of the case 102. In some embodiments, the primary liner 108 and
the reactive material liner 110 may be formed (e.g., contoured) to
substantially cover the explosive material 106 on a forward surface
of the explosive material 106 (i.e., the surface of the explosive
material 106 not encompassed by the case 102). For example, the
reactive material liner 110 may be formed to cover the forward
surface of the explosive material 106 in order to increase the
amount of pressure volume energy delivered to the reactive material
liner 110. The case 102 will tend to direct the pressure volume
energy generated by ignition of the explosive material 106 through
the open end of the case 102, thereby, imparting a substantial
amount of the pressure volume energy produced by this ignition to
the reactive material liner 110 and the primary liner 108 formed on
the reactive material liner 110. The pressure volume energy
delivered to the primary liner 108 and the reactive material liner
110 simultaneously deforms the primary liner 108 and the reactive
material liner 110 into a projectile 101 and propels the forming
projectile 101 at a velocity from the case 102.
[0032] An example of a projectile 101 formed by the EFP device 100
is shown in FIG. 1B. As discussed above, the size and geometry of
the projectile 101 may be dictated by the liners 108 and 110 formed
in the case 102 and the pressure volume energy delivered to the
liners 108 and 110 by the explosive material 106. Therefore, it is
noted that size and geometry of the projectile 101 shown in FIG. 1B
is to illustrate the present embodiment of the invention and is not
a limitation.
[0033] The pressure volume energy delivered to the primary liner
108 and the reactive material liner 110 deforms the liners 108 and
110 into a projectile shape such as the substantially elongated
shape shown in FIG. 1B. In some embodiments, the primary liner 108
may be deformed into an outer portion 126 of the substantially
concave projectile 101 and may partially surround the reactive
material liner 110. In some embodiments, the primary liner 108 may
partially surround the reactive material liner 110. The primary
liner 108 may deform to substantially form the anterior portion 122
(taken in the direction of projectile travel) of the projectile 101
and the reactive material liner 110 may deform into a central
portion 128 of the projectile 101. The primary liner 108 may deform
to extend longitudinally along the projectile 101 and a portion of
the deformed reactive material liner 110 may be exposed at the
posterior portion 124 (taken in the direction of projectile travel)
of the projectile 101. In some embodiments, the reactive material
liner 110 may comprise a material having a lower dynamic plastic
flow strength than that of the primary liner 108 in order to deform
into the central portion 128 of the projectile 101 while being
substantially surrounded by the deformed primary layer 108.
Additionally, the primary liner 108 may be deformed to provide
flanges 120 on the posterior portion 124 of the projectile 101. The
flanges 120 may extend in an outward direction from a longitudinal
axis of the projectile 101 and may be formed to enhance the
aerodynamic properties of the projectile 101, such as by providing
increased aerodynamic stability of the projectile 101 during
flight. It is noted that while the embodiment shown in FIG. 1B is
directed at a projectile 101 with the reactive material liner 110
deformed to be substantially disposed in a central portion 128 of
the projectile 101 substantially surrounded by the primary liner
101, the reactive material liner 110 may be formed in additional
configurations based on the relative amounts of liner material used
for liners 108 and 110, the shapes of the liners, the case, and the
explosive material. For example, the reactive material liner 110
may be disposed between two separate liners similar to the primary
liner 108 such that a projectile is formed having a reactive
material liner formed in a space between the two primary
liners.
[0034] In some embodiments, the reactive material liner 110 may
also be ignited as the primary liner 108 and the reactive material
liner 110 are expelled from the case 102. For example, the reactive
material liner 110 may be ignited by the shockwave created by the
detonation of the explosive material 106. As the projectile 101 is
formed, the reactive material liner 110 may start to combust. As
discussed above, the reactive material utilized in the reactive
material liner 110 may be formulated to provide a desired rate of
reaction or "burn rate" and may also, in some embodiments, contain
an ignition initiator to facilitate the ignition of the reactive
material. The combustion of the reactive material liner 110 may
form a propellant generated thrust such as a propulsive jet 118
shown in FIG. 1B. For example, as the projectile 101 completes
formation, a portion of the reactive material liner 110 is ignited.
The ignition of the reactive material liner 110 produces a reaction
force such as the thrust generated by the propulsive jet 118 in a
direction substantially opposite to the direction in which the
projectile 101 is propelled by the explosive material 106. In some
embodiments, the primary liner 108 may form at least partially
around the posterior portion 124 of the projectile 101. The
deformed primary liner 108 may reduce the flow rate and thrust from
the reactive material liner 110 ignited by the shockwave impulse
and may decrease the size of the propulsive jet 118 formed by the
combustion of the reactive material of the reactive material liner
110 at the posterior portion 124 of the projectile 101.
[0035] The thrust produced by the reactive material in the reactive
material liner 110 may increase the velocity of the projectile 101
during the flight of the projectile 101 after it has been expelled
from the case 102 at an initial velocity and before the projectile
101 impacts a target. For example, an EFP device 100 may be formed
to produce a projectile 101 having an initial velocity of 2.2 km/s.
That is, the ignition of the explosive material 106 may form a
projectile 101 from the primary liner 108 and the reactive material
liner 110 and propel the liners 108 and 110 toward a target at an
initial velocity of 2.2 km/s. As will be appreciated by one with
ordinary skill in the art, aerodynamic drag will reduce the initial
velocity of the projectile 101 as the projectile 101 travels toward
the target. In some embodiments, the thrust produced by the
ignition of the reactive material may increase the velocity of
projectile 101 ten to forty percent (10% to 40%) higher than the
initial velocity provided by the pressure volume energy imparted to
liners 108 and 110. By way of example and not limitation, the
ignition of the reactive material liner 110 may further increase
the velocity of the explosively formed projectile 101 to a velocity
of 2.75 km/s (i.e., approximately a 25% increase in velocity). The
higher velocity of the projectile 101 may increase the range and
destructive capability of the projectile 101 such as perforation
capability and behind-armor debris effects. Additionally, upon
impact with the target, any reactive material of the reactive
material liner 110 that has not been burned to propel the
projectile 101 may produce a high burst of energy, further
increasing the destructive capability of the projectile 101. It is
noted that while the embodiment shown and described with reference
to FIG. 1A and 1B illustrates a projectile 101 having a primary
liner 108 forming an anterior portion 122 of the projectile, the
primary liner 108 may form a posterior portion 124 of the
projectile 101. For example, in a forward folding explosively
formed projectile, the primary liner may be disposed on the forward
surface of the explosive material and the reactive material liner
may be disposed on the forward surface of the primary liner. After
initiation of the explosive material, the primary liner may foiiii
a posterior portion of the projectile and a propulsive jet of the
reactive material liner may be formed through a hole in the primary
liner.
[0036] An additional embodiment of the present invention is shown
in FIGS. 2A and 2B. The EFP device 200 shown in FIG. 2A is
substantially similar to the EFP device 100 previously described
with reference to FIG. 1A, and may include a case 202, an initiator
204, an explosive material 206, and a primary liner 208. The case
202, initiator 204, explosive material 206, and primary liner 208
may comprise similar materials and configurations as discussed
above in reference to the EFP device 100. The EFP device 200 may
also comprise a second liner such as a reactive material liner 210
similar to the above described reactive material liner 110. The EFP
device 200 may further include a third, control liner 212
comprising a control material. The control liner 212 may comprise a
material configured and formulated to control (i.e., enhancing or
impeding) the rate of reaction of the reactive material liner 210.
For example, the control liner 212 may be formed on the forward
surface of the explosive material 206 and may comprise a material
such as a polymer, metal, metal alloy, ceramics, etc. The polymer
materials may include polymethylmethacrylate (PMMA), acrylonitrile
butadiene styrene (ABS), polybutylene terephthalate (PBT), a
photopolymer, etc. The metal materials may include copper, steel,
aluminum, etc. that are nonporous and porous. The ceramics may
include boron carbide, alumina, tungsten carbide, etc. In some
embodiments, the control liner 212 may comprise a substantially
inert material that may tend not to react with the reactive
material liner 210. In some embodiments, control liner 212 may
comprise a material that may react with the combusting explosive
material 206. The control liner 210 may have a thickness, for
example, measuring 2.54 mm (approximately 0.10 inches).
[0037] As shown in FIG. 2B, the pressure volume energy delivered to
the primary liner 208, the reactive material liner 210, and the
control liner 212 may deform the liners 208, 210, and 212 into a
projectile shape such as a substantially elongated shape. In some
embodiments, the primary liner 208 may be deformed into an outer
portion 226 of the substantially elongated projectile 201 and may
at least partially surround the reactive material liner 210 and the
control liner 212. The primary liner 208 may deform to
substantially form the anterior portion 222 (taken in the direction
of projectile travel) of the projectile 201 and the reactive
material liner 210 and the control liner 212 may deform into a
central portion 228 of the projectile 201. In some embodiments, a
portion of the reactive material liner 210 may be exposed at the
posterior portion 224 of the projectile 201. In some embodiments,
the reactive material liner 210 and the control liner 212 may
comprise materials having a lower dynamic plastic flow strength
than that of the primary liner 208 in order to deform into the
central portion 228 of the projectile 201 substantially surrounded
by the deformed primary layer 208. Additionally, the primary liner
208, the control liner 212, or both the primary liner 208, the
control liner 212 may be deformed to provide flanges 220 on the
posterior portion 224 of the projectile 201.
[0038] Similar in manner to performance of the previously described
EFP device 100, the reactive material liner 210 may also be ignited
as the primary liner 208, the reactive material liner 210, and the
control liner 212 are expelled from the case 202. In some
embodiments, the control liner 212 may control the rate of reaction
of the reactive material in the reactive material liner 210. For
example, the control liner 212 may mitigate or reduce the shock
pressure imparted to reactive material liner 210 from the
detonation of explosive material 206 and may decrease the
combustion rate of the reactive material ignited by the shockwave
impulse. In some embodiments, the control liner 212 may decrease
the size of the propulsive jet 218 formed by the combustion of the
reactive material of the reactive material liner 210 at the
posterior portion 224 of the projectile 210. The shape, size, and
thickness of the control liner 212 formed in the case 201 may be
varied to control the size of the propulsive jet 218 of the
projectile 201 and produce the desired velocity increase provided
by the ignited reactive material following the formation of the
projectile 201 .
[0039] An additional embodiment of the present invention is shown
in FIGS. 3A and 3B. The EFP device 300 shown in FIG. 3A is
substantially similar to the EFP devices 100 and 200 previously
described with reference to FIGS. 1A and 2A, respectively, and may
include a case 302, an initiator 304, an explosive material 306,
and a primary liner 308. The case 302, initiator 304, explosive
material 306, and primary liner 308 may comprise similar materials
and configurations as discussed above in reference to the EFP
devices 100 and 200. The EFP device 300 may also include a second
liner such as a reactive material liner 310 and a control liner 312
similar to the reactive material liners 110 and 210 previously
described with reference to FIGS. 1A and 2A and the control liner
212 described with reference to FIG. 2A.
[0040] The EFP device 300 may further include a fourth liner
comprising an additional reactive material and a fifth, buffer
liner comprising a buffer material. The buffer liner 314 may
comprise a material configured and formulated to separate the
reactive material liner 310 and the additional reactive material
liner 316. The buffer liner 314 may be formed in between the
reactive material liner 310 from the additional reactive material
liner 316 in the case 302. The buffer liner 314 may comprise a
material such as a polymer, metal, metal alloy, ceramic, etc. In
some embodiments, the buffer liner 314 may comprise a substantially
inert material that will tend to not react with the reactive
material liner 310. The reactive material liner 310 and the
additional reactive material liner 316 may comprise the same
reactive material or the reactive material liner 310 may comprise a
first reactive material composition while the additional reactive
material liner 316 comprises a different second reactive material
composition. The additional reactive material liner 316 may
comprise materials similar to the reactive material liners 110 and
210 previously described with reference to FIGS. 1A and 2A.
[0041] As shown in FIG. 3B, the pressure volume energy delivered to
the primary liner 308, the reactive material liner 310, the buffer
liner 314, the additional reactive material liner 316, and the
control liner 312 by the explosive material 306 deforms the liners
308, 310, 312, 314, and 316 into a projectile shape such as a
substantially elongated shape. In some embodiments, the primary
liner 308 may be deformed into an outer portion 326 of the
substantially concave projectile 301 and may at least partially
surround the reactive material liner 310, the buffer liner 314, the
additional reactive material liner 316, and the control liner 312.
The primary liner 308 may deform to substantially form the anterior
portion 322 (taken in the direction of projectile travel) of the
projectile 301 and the reactive material liner 310, the buffer
liner 314, the additional reactive material liner 316, and the
control liner 312 may deform into a central portion 328 of the
projectile 301. The reactive material layer 310 may be
substantially disposed at the posterior portion 324 of the
projectile 301. The buffer layer 314 may be disposed between the
reactive material liner 310 and the additional reactive material
liner 316. In some embodiments, a portion of the reactive material
liner 310 may be exposed at the posterior portion 324 of the
projectile 301. In some embodiments, the reactive material liner
310, the buffer liner 314, the additional reactive material liner
316, and the control liner 312 may comprise materials having a
lower dynamic plastic flow strength than that of the primary liner
308 in order to deform into the central portion 328 of the
projectile 301 substantially surrounded by the deformed primary
layer 308. Additionally, the primary liner 308, the control liner
312, or both the primary liner 308, the control liner 312 may be
deformed to provide flanges 320 on the posterior portion of the
projectile 301.
[0042] 100421 In a manner similar to the actuation of the EFP
assemblies 100 and 200, previously described with reference to
FIGS. 1A and 2A, respectively, the reactive material liner 310 may
be ignited as the reactive material liner 310, the buffer liner
314, the additional reactive material liner 316, and the control
liner 312 are expelled from the case 302. The buffer liner 314 may
act to buffer the additional reactive material liner 316 from the
reactive material liner 310. The separation of the reactive
material liner 310 from the additional reactive material liner 316
allows the reactive material liner 310 to be ignited in order to
increase the velocity of the projectile 301 after being explosively
expelled from the case 302. The buffer liner 314 acts to inhibit
the additional reactive material liner 316 from igniting during the
formation of the projectile 301. The unspent reactive material of
both the reactive material liner 310 and the additional reactive
material liner 316 may produce a high burst of energy both thermal
and mechanical further increasing the destructive capability of the
projectile 301 upon impact with the target.
[0043] FIGS. 4A and 4B are, respectively, longitudinal
cross-sectional views of a yet another embodiment of an EFP device
400 including a reactive material liner 410 for generating an
explosively formed projectile 401 and an explosively formed
projectile 401 resulting from initiation of the device 400. The EFP
device 400 shown in FIG. 4A is substantially similar to the EFP
device 100 previously described with reference to FIG. 1A, and may
include a case 102, an initiator 104, an explosive material 106,
and a primary liner 408. The primary liner 408 may be disposed on
the forward surface of the explosive material 106 and the reactive
material liner 410 may be disposed on the forward surface of the
primary liner 408. The EFP device 400 may form the forward folding
explosively formed projectile 401 (i.e., the primary liner 408
folds around the reactive material 410 toward the direction of
projectile travel) shown in FIG. 4B. For example, after initiation
of the explosive material 106, the primary liner 408 may form a
posterior portion 124 of the projectile 401. The primary liner 410
may surround the reactive material 410 and the end portions of the
primary liner 408 may form the anterior portion 122 of the
projectile 401. A propulsive jet 118 of the reactive material liner
410 may be formed through a hole 403 in the primary liner 408.
[0044] The following examples serve to explain embodiments of the
present invention in more detail. These examples are not to be
construed as being exhaustive or exclusive, or otherwise limiting,
as to the scope of this invention.
EXAMPLES
Example 1
[0045] Explosively Formed Projectile Testing using a First Epoxy
Based Reactive Material and a Stereolithographic Polymer
[0046] A first velocity test was performed on an EFP device similar
to the EFP device shown in FIG. 2. The testing assembly included an
EFP device mounted on polystyrene foam blocks and an alloy steel
plate (AR400) target located 10 feet (3.048 meters) from the EFP
device. Two X-ray stations with film cassettes were located between
the EFP device and the target to obtain the profile and velocity of
the projectile formed by the EFP device in flight. The first X-ray
station was located 4 feet (1.219 meters) from the EFP device and
the second X-ray station was located 9 feet (2.743 meters) from the
EFP device. A high-speed digital camera was located at the target
to record the projectile impact.
[0047] The EFP device was fabricated from a modified Selectable
Lightweight Attack Munitions (SLAM) warhead manufactured by the
Alliant Techsystems (ATK) Corporation of Minneapolis, Minnesota.
The explosive material and liners in the SLAM warhead included a
LX-14 explosive material weighing 256.9 grams formed within the
case. The SLAM warhead also consisted of a primary liner and a
reactive material liner. The primary liner was formed from copper
having a weight of 44 grams and an average axial thickness of
0.0366 inches (0.923 millimeters). The reactive material liner was
formed from a first epoxy based reactive material having a weight
of 44.6 grams, a density of 6.080 g/cc, and an average axial
thickness of 0.0543 inches (1.379 millimeters). The first epoxy
based reactive material comprised 71.434 percent by weight tungsten
(about 50.004 percent tungsten having a particle size of about 90
.mu.m and 21.430 percent tungsten having a particle size of about 6
to 8 .mu.m), 9.988 percent by weight potassium perchlorate, about
9.988 percent by weight zirconium and 8.590 percent by weight of an
epoxy material. The epoxy material included 4.419 percent by weight
Araldite.RTM. LY 1556, 3.977 percent by weight Aradur.RTM. 917,
0.023 percent by weight Accelerator DY 070 (each of which are
commercially available from Huntsman Advanced Materials of
Brewster, N.Y.), and 0.171 percent by weight cabosil. The control
liner was formed from a sterolithographic polymer having a weight
of 15.3 grams, a density of 1.12 g/cc, and an average axial
thickness of 0.1000 inches (2.54 millimeters). In the test, the
sterolithographic polymer was formed from a liquid photopolymer
manufactured under the trade name WATERSHED.TM. 11120 and
commercially available from the DMS SOMOS.RTM. Corporation of New
Castle, Del.
[0048] The predicted velocity for the tested EFP projectile without
any assist from the reactive material was 2.24 km/s. The measured
velocity just prior to impact with the target measured with the
high-speed digital camera was 2.68 km/s.
[0049] The results of the first velocity test on the projectile
formed by the EFP device having a first epoxy based reactive
material liner and a stereolithographic polymer control liner
indicated that the projectile including the reactive material
exhibited a velocity greater than the predicted velocity of the
projectile.
Example 2
[0050] Explosively Formed Projectile Testing using a Second Epoxy
Based Reactive Material and a Stereolithographic Polymer
[0051] A second velocity test was performed on an EFP device
similar to the EFP device shown in FIG. 2. The testing assembly was
similar to the test in Example 1 except an additional X-ray station
located at the EFP device was added to obtain the profile and
velocity of the projectile just after the projectile had been
formed by the EFP device.
[0052] The EFP device was fabricated from a SLAM warhead that
included a 256.9 gram LX-14 explosive material formed in the case,
a primary liner, and a reactive material liner. The primary liner
was formed from copper having a weight of 44 grams and an average
axial thickness of 0.0366 inches (0.923 millimeters). The reactive
material liner was formed from a second epoxy based reactive
material having a weight of 47.6 grams, a density of 6.552 g/cc,
and an average axial thickness of 0.0504 inches (1.280
millimeters). The second epoxy based reactive material comprised
72.112 percent by weight tungsten (50.478 percent tungsten having a
particle size of about 90 .mu.m and 21.634 percent tungsten having
a particle size of about 6 to 8 .mu.m), 10.000 percent by weight
nickel, 10.000 percent by weight aluminum and 7.888 percent by
weight of an epoxy material. The epoxy material included 4.088
percent by weight Araldite.RTM. LY 1556, 3.680 percent by weight
Aradur.RTM. 917, 0.021 percent by weight Accelerator DY 070 (each
of which are commercially available from Huntsman Advanced
Materials of Brewster, N.Y.), and 0.100 percent by weight cabosil.
The control liner was formed from a sterolithographic polymer
having a weight of 15.3 grams, a density of 1.12 g/cc, and an
average axial thickness of 0.1000 inches (2.54 millimeters). In the
test, the sterolithographic polymer was the same as the polymer
used in Example 1.
[0053] The predicted velocity for the projectile formed by the EFP
device without any assist from the reactive material is 2.19 km/s.
The measured velocity just after formation of the projectile was
approximately 2.20 km/s. The measured velocity at the first X-ray
station was 2.72 km/s.
[0054] Similar to Example 1, the results of the second velocity
test on the projectile formed by the EFP device having a second
epoxy based reactive material liner and a stereolithographic
polymer control liner indicated that the projectile including the
reactive material exhibited a velocity greater than the predicted
velocity of the projectile and exhibited a velocity greater than
the measured velocity just after formation.
[0055] In view of the above, embodiments of the present invention
may be particularly useful in producing EFPs enhanced by reactive
materials. The ignition of the reactive material creating a
propulsive jet may be used to increase the velocity of an EFP
beyond the initial velocity produced by the ignition of the
explosive material in the case. Conventionally, the amount of
explosives in the case along with the material properties of the
liners and case inhibit the amount of energy that may be delivered
to the liners. The ability to increase the velocity of a projectile
after the projectile has been formed with an initial velocity
imparted by the explosive material will enable the projectile to
obtain velocities not attainable previously in similar, but
conventional, EFP device configurations. The higher velocity of the
projectile may increase the range and destructive capability of the
projectile such as perforation capability and the behind-armor
debris effects. The ignition of the reactive material provides a
relatively lower g-force acceleration of the projectile than the
explosive material and may accelerate the projectile without
substantially damaging or breaking up the formed projectile.
Further, the combustion of the reactive material may provide a
tracer effect on the projectile during its flight.
[0056] While the present invention has been described herein with
respect to certain preferred embodiments, those of ordinary skill
in the art will recognize and appreciate that it is not so limited.
Rather, many additions, deletions and modifications to the
preferred embodiments may be made without departing from the scope
of the invention as hereinafter claimed, and legal equivalents. In
addition, features from one embodiment may be combined with
features of another embodiment while still being encompassed within
the scope of the invention as contemplated by the inventors.
* * * * *