U.S. patent application number 12/466456 was filed with the patent office on 2010-11-18 for systems and methods to produce forged powder metal parts with transverse features.
This patent application is currently assigned to GM GLOBAL TECHNOLGOY OPERATIONS, INC.. Invention is credited to Edward P. Becker, Anil K. Sachdev.
Application Number | 20100290942 12/466456 |
Document ID | / |
Family ID | 43068648 |
Filed Date | 2010-11-18 |
United States Patent
Application |
20100290942 |
Kind Code |
A1 |
Becker; Edward P. ; et
al. |
November 18, 2010 |
SYSTEMS AND METHODS TO PRODUCE FORGED POWDER METAL PARTS WITH
TRANSVERSE FEATURES
Abstract
Systems and methods produce forged powder metal parts
respectively comprising a transverse feature. A system may comprise
a powder metal die, a sintering oven, a forging apparatus, a core
material, and a powder metal. The powder metal die may receive and
compact the core material and the powder metal to form a compacted
powder metal part with at least a portion of the core material
embedded therein to define a transverse feature in the compacted
powder metal part. The sintering oven may receive and sinter the
compacted powder metal part with the core material remaining
embedded therein to maintain the definition of the transverse
feature during sintering. The forging apparatus may receive and
forge the sintered powder metal part with the core material
remaining embedded therein to maintain the definition of the
transverse feature during forging with the embedded core material
being removable from the forged powder metal thereafter.
Inventors: |
Becker; Edward P.;
(Brighton, MI) ; Sachdev; Anil K.; (Rochester
Hills, MI) |
Correspondence
Address: |
DINSMORE & SHOHL LLP
FIFTH THIRD CENTER, ONE SOUTH MAIN STREET, SUITE 1300
DAYTON
OH
45402
US
|
Assignee: |
GM GLOBAL TECHNOLGOY OPERATIONS,
INC.
Detroit
MI
|
Family ID: |
43068648 |
Appl. No.: |
12/466456 |
Filed: |
May 15, 2009 |
Current U.S.
Class: |
419/5 ;
425/78 |
Current CPC
Class: |
B22F 2998/10 20130101;
B22F 2998/10 20130101; B22F 3/10 20130101; B22F 3/17 20130101; B22F
3/02 20130101; B22F 5/10 20130101 |
Class at
Publication: |
419/5 ;
425/78 |
International
Class: |
B22F 3/12 20060101
B22F003/12; B22F 3/24 20060101 B22F003/24 |
Claims
1. A method of producing a forged powder metal part comprising a
transverse feature, the method comprising: providing a powder metal
die; positioning a core material in the die; filling the die at
least partially with a powder metal to at least partially cover the
core material with the powder metal; compacting with the die the
powder metal to form a compacted powder metal part with at least a
portion of the core material embedded therein, wherein the embedded
core material defines a transverse feature formed in the compacted
powder metal part; sintering the compacted powder metal part to
form a sintered powder metal part with the core material remaining
embedded therein to maintain the definition of the transverse
feature during the sintering of the compacted powder metal part;
forging the sintered powder metal part to form a forged powder
metal part with the core material remaining embedded therein to
maintain the definition of the transverse feature during the
forging of the sintered powder metal part; and removing the
embedded core material from the forged powder metal part.
2. The method of claim 1, wherein the core material is
frangible.
3. The method of claim 2, wherein the frangible core material is
sufficiently brittle so as to be at least partially pulverized
during the forging of the sintered powder metal part.
4. The method of claim 2, wherein the frangible core material is at
least partially broken during the forging of the sintered powder
metal part.
5. The method of claim 4, wherein the frangible core material
comprises a degree of resiliency sufficient such that the at least
partially broken frangible core material maintains the definition
of the transverse feature during the forging of the sintered powder
metal part.
6. The method of claim 1, wherein the core material comprises at
least one of graphite and ceramic.
7. The method of claim 1, wherein the core material does not melt,
vaporize, infiltrate, or otherwise dissipate during the compacting
of the powder metal, the sintering of the compacted powder metal
part, and the forging of the sintered powder metal part, and any
combination thereof.
8. The method of claim 1, wherein the core material is positioned
in the die prior to the filling of the die with the powder
metal.
9. The method of claim 1, wherein the core material is positioned
in the die during the filling of the die with the powder metal.
10. The method of claim 1, wherein the embedded core material is
removed from the forged powder metal part via at least one of a
shaking, a reaming, a brushing, and an air blowing of the forged
powder metal part.
11. The method of claim 1, wherein the transverse feature comprises
a depression of any one or more shapes, sizes, and dimensions in
the forged powder metal part.
12. The method of claim 11, wherein the transverse feature
comprises at least one of a hole, a groove, a passage, a recess, an
indentation, a thread, a cavity, an undercut, a crosscut, and an
impression.
13. The method of claim 1, wherein the forged powder metal part
comprises a connecting rod of a reciprocating piston engine and the
transverse feature comprises a lubricant passage between a crank
end and a piston end of the connecting rod.
14. The method of claim 13, wherein the lubricant passage connects
the crank end and the piston end of the connecting rod so as to
permit passage of a lubricant there-between.
15. A method of producing a forged powder metal part comprising a
transverse feature, the method comprising: providing a powder metal
die; positioning a frangible core material in the die; filling the
die at least partially with a powder metal to at least partially
cover the frangible core material with the powder metal; compacting
with the die the powder metal to form a compacted powder metal part
with at least a portion of the frangible core material embedded
therein, wherein the embedded frangible core material defines a
transverse feature formed in the compacted powder metal part;
sintering the compacted powder metal part to form a sintered powder
metal part, wherein the frangible core material remains embedded
therein and does not melt, vaporize, infiltrate, or otherwise
dissipate during the sintering so as to maintain the definition of
the transverse feature during the sintering of the compacted powder
metal part; forging the sintered powder metal part to form a forged
powder metal part with the frangible core material remaining
embedded therein to maintain the definition of the transverse
feature during the forging of the sintered powder metal part; and
removing the embedded frangible core material from the forged
powder metal part.
16. A system to produce a forged power metal part comprising a
transverse feature, the system comprising a powder metal die, a
sintering oven, a forging apparatus, a core material, and a powder
metal, wherein: the powder metal die is operable to receive and
compact the core material and the powder metal to form a compacted
powder metal part with at least a portion of the core material
embedded therein, wherein the embedded core material defines a
transverse feature formed in the compacted powder metal part; the
sintering oven is operable to receive and sinter the compacted
powder metal part to form a sintered powder metal part with the
core material remaining embedded therein to maintain the definition
of the transverse feature during a sintering of the compacted
powder metal part by the sintering oven; and the forging apparatus
is operable to receive and forge the sintered powder metal part to
form a forged powder metal part with the core material remaining
embedded therein to maintain the definition of the transverse
feature during a forging of the sintered powder metal part by the
forging apparatus, wherein the embedded core material is removable
from the forged powder metal.
17. The system of claim 16, wherein the core material is frangible
and is at least partially broken during the forging of the sintered
powder metal part.
18. The system of claim 17, wherein the frangible core material
comprises a degree of resiliency sufficient such that the at least
partially broken frangible core material maintains the definition
of the transverse feature during the forging of the sintered powder
metal part by the forging apparatus.
19. The system of claim 16, wherein the core material does not
melt, vaporize, infiltrate, or otherwise dissipate during the
compacting of the powder metal, the sintering of the compacted
powder metal part, and the forging of the sintered powder metal
part, and any combination thereof.
20. The system of claim 16, wherein the core material comprises at
least one of graphite and ceramic.
Description
BACKGROUND
[0001] The present invention relates generally to powder metal
parts with transverse features. More particularly, the invention
relates to systems and methods to produce forged powder metal parts
with transverse features.
[0002] Conventional systems and methods of the prior art to produce
powder metal parts having transverse features utilize core
materials to define the transverse features during compacting and
sintering phases of powder metal part manufacturing processes. The
utilized core materials, however, are formed substantially of
matter(s) that has a melting point lower than fusion temperatures
of the powder metal achieved during sintering phases. As such, the
core material melts, vaporizes, and/or infiltrates the powder metal
part during sintering phases. Such matter(s) forming the core
materials typically include copper and/or zinc. With the melting,
vaporization, and/or infiltration of the core material into the
powder metal part, the transverse feature is provided therein as a
void region.
[0003] Such conventional systems and methods, however, are not
suitable for powder metal parts to be forged. Forging strengthens
powder metal parts such that forged powder metal parts typically
are stronger than cast or machined metal parts. Powder metal parts
produced according to conventional systems and methods where the
core material is melted, vaporized, and/or infiltrated into the
part are subject to deformation. More particularly, the void region
defining the transverse feature formerly defined and occupied by
the core material prior to sintering, generally at least partially
collapses during forging since the core material is absent from the
void region, leaving nothing to prevent the metal from filling the
void region when subjected to the compressive forces commonly
associated with forging processes. Other conventional approaches
that do not utilize core materials to define transverse features in
powder metal parts typically require completion of machining
operations of the parts, which often is difficult, time-consuming,
and costly. As such, based on the foregoing, there exists a need
for systems and methods that utilize core materials to produce
forged powder metal parts with transverse features and that do not
require completion of subsequent machining.
SUMMARY
[0004] It is against the above background that embodiments of the
present invention generally relate to systems and methods that
utilize core materials to produce forged powder metal parts with
transverse features.
[0005] In accordance with one embodiment, a method of producing a
forged powder metal part comprising a transverse feature comprises
providing a powder metal die and positioning a core material in the
die. The method also comprises filling the die at least partially
with a powder metal to at least partially cover the core material
with the powder metal and compacting with the die the powder metal
to form a compacted powder metal part with at least a portion of
the core material embedded therein, wherein the embedded core
material defines a transverse feature formed in the compacted
powder metal part. Thereafter, the method comprises sintering the
compacted powder metal part to form a sintered powder metal part
with the core material remaining embedded therein to maintain the
definition of the transverse feature during the sintering of the
compacted powder metal part and forging the sintered powder metal
part to form a forged powder metal part with the core material
remaining embedded therein to maintain the definition of the
transverse feature during the forging of the sintered powder metal
part. Following the forging of the powder metal part, the method
comprises removing the embedded core material from the forged
powder metal part.
[0006] Optionally, the core material may be frangible. The
frangible core material may be sufficiently brittle so as to be at
least partially pulverized during the forging of the sintered
powder metal part. The frangible core material may be at least
partially broken during the forging of the sintered powder metal
part. The frangible core material may comprise a degree of
resiliency sufficient such that the at least partially broken
frangible core material maintains the definition of the transverse
feature during the forging of the sintered powder metal part.
Further, the core material may comprise at least one of graphite
and ceramic. The core material may not melt, vaporize, infiltrate,
or otherwise dissipate during the compacting of the powder metal,
the sintering of the compacted powder metal part, and the forging
of the sintered powder metal part, and any combination thereof. The
core material may be positioned in the die prior to the filling of
the die with the powder metal or may be positioned in the die
during the filling of the die with the powder metal. The embedded
core material may be removed from the forged powder metal part via
at least one of a shaking, a reaming, a brushing, and an air
blowing of the forged powder metal part.
[0007] Further, optionally, the transverse feature may comprises a
depression of any one or more shapes, sizes, and dimensions in the
forged powder metal part. The transverse feature may comprise at
least one of a hole, a groove, a passage, a recess, an indentation,
a thread, a cavity, an undercut, a crosscut, and an impression. The
forged powder metal part may comprise a connecting rod of a
reciprocating piston engine and the transverse feature comprises a
lubricant passage between a crank end and a piston end of the
connecting rod. The lubricant passage may connect the crank end and
the piston end of the connecting rod so as to permit passage of a
lubricant there-between.
[0008] In accordance with another embodiment, a method of producing
a forged powder metal part comprising a transverse feature
comprises providing a powder metal die and positioning a frangible
core material in the die. The method also comprises filling the die
at least partially with a powder metal to at least partially cover
the frangible core material with the powder metal. Thereafter, the
method comprises compacting with the die the powder metal to form a
compacted powder metal part with at least a portion of the
frangible core material embedded therein, wherein the embedded
frangible core material defines a transverse feature formed in the
compacted powder metal part, sintering the compacted powder metal
part to form a sintered powder metal part, wherein the frangible
core material remains embedded therein and does not melt, vaporize,
infiltrate, or otherwise dissipate during the sintering so as to
maintain the definition of the transverse feature during the
sintering of the compacted powder metal part, and forging the
sintered powder metal part to form a forged powder metal part with
the frangible core material remaining embedded therein to maintain
the definition of the transverse feature during the forging of the
sintered powder metal part. The method further comprises removing
the embedded frangible core material from the forged powder metal
part.
[0009] In accordance with yet another embodiment, a system to
produce a forged power metal part comprising a transverse feature
comprises a powder metal die, a sintering oven, a forging
apparatus, a core material, and a powder metal. The powder metal
die is operable to receive and compact the core material and the
powder metal to form a compacted powder metal part with at least a
portion of the core material embedded therein, wherein the embedded
core material defines a transverse feature formed in the compacted
powder metal part. The sintering oven is operable to receive and
sinter the compacted powder metal part to form a sintered powder
metal part with the core material remaining embedded therein to
maintain the definition of the transverse feature during a
sintering of the compacted powder metal part by the sintering oven.
The forging apparatus is operable to receive and forge the sintered
powder metal part to form a forged powder metal part with the core
material remaining embedded therein to maintain the definition of
the transverse feature during a forging of the sintered powder
metal part by the forging apparatus. The embedded core material is
removable from the forged powder metal.
[0010] Optionally, the core material may be frangible and may be at
least partially broken during the forging of the sintered powder
metal part. The frangible core material may comprise a degree of
resiliency sufficient such that the at least partially broken
frangible core material maintains the definition of the transverse
feature during the forging of the sintered powder metal part by the
forging apparatus. The core material may not melt, vaporize,
infiltrate, or otherwise dissipate during the compacting of the
powder metal, the sintering of the compacted powder metal part, and
the forging of the sintered powder metal part, and any combination
thereof. The core material may comprise at least one of graphite
and ceramic.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The following detailed description of specific embodiments
can be best understood when read in conjunction with the following
drawings, where like structure is indicated with like reference
numerals and in which:
[0012] FIG. 1 illustrates a system to produce a forged powder metal
part with a transverse feature according to one embodiment of the
present invention; and
[0013] FIG. 2 illustrates a cross-sectional view of a connecting
rod forged powder metal part produced according to an embodiment of
the present invention.
[0014] The embodiments set forth in the drawings are illustrative
in nature and are not intended to be limiting of the embodiments
defined by the claims. Moreover, individual aspects of the drawings
and the embodiments will be more fully apparent and understood in
view of the detailed description that follows.
DETAILED DESCRIPTION
[0015] As mentioned above, embodiments of the present invention
relate generally to systems and methods that utilize core materials
to produce forged powder metal parts with transverse features. As
used herein, "transverse features" include, but are not limited to,
depressions of any one or more shapes, sizes, and dimensions in
forged powder metal parts. Such depressions, and, thus, transverse
features, may include, but are not limited to, holes, grooves,
passages, recesses, indentations, threads, cavities, undercuts,
crosscuts, and impressions. Further, as used herein, "powder metal"
may include, but is not limited to, an aluminum, a titanium, an
iron, a steel, a brass, a stainless steel, a bronze, any alloys
thereof, and any combination thereof.
[0016] Referring initially to FIG. 1, one embodiment of the present
invention relates to a system 10 to produce a forged powder metal
part 28 comprising a transverse feature. The system 10 comprises a
powder metal 12, a core material 14, a powder metal die 16, a
sintering oven 20, and a forging apparatus 24. As mentioned above,
the powder metal 12 may comprise at least one of a variety of
metals and alloys thereof. The core material 14 is at least
partially embedded into the powder metal during compacting,
sintering, and forging thereof. The embedded core material shapes
the powder metal accordingly. More particularly, the core material
14 defines the shapes, sizes, and dimensions of a transverse
feature formed in the powder metal 12 through the compacting,
sintering, and forging thereof by the system 10.
[0017] The core material 14 is configured at least substantially of
a material that does not melt, vaporize, infiltrate, or otherwise
dissipate during the compacting, sintering, and forging, and any
combination thereof, of the powder metal 12. Thus, the core
material 14 comprises a melting temperature higher than the fusion
temperature of the powder metal during sintering thereof. Such
materials include, but are not limited to, graphite and ceramic.
Thus, in one embodiment, the core material 14 comprises at least
one of graphite and ceramic. As used herein, "dissipate" refers
generally to a withdrawal of the core material 14 from the formed
transverse feature. For example, a core material that melts or
vaporizes may infiltrate the powder metal and, thereby, no longer
be confined to the transverse feature formed by the core
material.
[0018] The powder metal die 16 may be any conventional die known or
later developed in the art that is operable to compact the powder
metal as described herein. The powder metal die 16 is operable to
receive the powder metal 12 and the core material 14. The core
material 14 is positioned in the die 16 according to a desired
position for the transverse feature to be formed in the powder
metal 12. The core material 14 may be positioned in the die 16
either prior to or during the filling of the die 16 with the powder
metal 12. The die 16 is filled at least partially with the powder
metal 12 so that the core material 14 is at least partially covered
with the powder metal 12. The die 16 also is operable to compact
the core material 14 and the powder metal 12 positioned therein.
The die 16 compacts the core material 14 and the powder metal 12 to
form a compacted metal part 18 with at least a portion of the core
material embedded therein. The embedded core material defines the
transverse feature formed in the compacted powder metal part
18.
[0019] The sintering oven 20 is operable to receive and sinter the
compacted powder metal part 18 with the embedded core material.
Thereby, the sintering oven 20 forms a sintered powder metal part
22 with the embedded core material remaining embedded therein. As
such, the embedded core material maintains the definition of the
transverse feature during the sintering of the compacted powder
metal part 18 by the sintering oven 20.
[0020] The forging apparatus 24 is operable to receive and forge
the sintered powder metal part 22 with the embedded core material.
Thereby, the forging apparatus 24 forms a forged powder metal part
26 with the embedded core material remaining embedded therein. As
such, the embedded core material maintains the definition of the
transverse feature during the forging of the sintered powder metal
part 22 by the forging apparatus 24. The embedded core material is
removable from the forged powder metal part 26 to produce a forged
powder metal part 28 with an exposed transverse feature. The
embedded core material may be removed, generally after sufficiently
cooling, from the forged powder metal part 26 via at least one of a
shaking, a brushing, and an air blowing of the forged powder metal
part 26 to result in the forged powder metal part 28 with the
exposed transverse feature.
[0021] The core material 14 may be frangible such that it is
sufficiently brittle so as to be at least partially pulverized
during the forging of the sintered powder metal part 22 by the
forging apparatus 24. For example, the frangible core material may
be at least partially broken during the forging of the sintered
powder metal part 22. The frangible core material may comprise a
degree of resiliency sufficient such that the at least partially
broken core material maintains the definition of the transverse
feature during the forging of the sintered powder metal part. A
breaking of the core material into smaller parts may facilitate the
removal of the embedded core material from the powder metal part
following completion of forging processes.
[0022] The presence of the embedded core material in the sintered
powder metal part substantially prevents closure of the transverse
feature during forging processes. Otherwise, should the embedded
core material melt, vaporize, dissipate, or otherwise be removed
from the transverse feature, the compressive forces applied to
powder metal parts by forging apparatuses during forging processes
generally is sufficient to cause the powder metal to collapse and
at least partially fill in the transverse feature abandoned by the
core material.
[0023] It is contemplated by the present inventors that the forged
powder metal part 28 with the transverse feature may any part
attainable with an embodiment of the present invention. In one
embodiment, for example, as shown in FIG. 2, the forged powder
metal part 28 comprises a connecting rod 30 of a reciprocating
piston engine and the transverse feature 32 comprises a lubricant
passage 34 between a crank end 36 and a piston end 38 of the
connecting rod 30. The lubricant passage 34 may connect the crank
end 36 and the piston end 38 of the connecting rod 30 so as to
permit passage of a lubricant there-between.
[0024] Additional embodiments of the present invention relate
generally to methods of producing forged powder metal parts with
transverse features. In accordance with one such embodiment, a
method produces a forged powder metal part comprising a transverse
feature, as follows: position a core material in a powder metal
die; fill the die at least partially with a powder metal such that
the core material is at least partially covered thereby; operate
the die to compact the powder metal and the core material to form a
compacted powder metal part with at least a portion of the core
material embedded therein so that the embedded core material
defines a transverse feature in the compacted powder metal part;
position the compacted powder metal part with the embedded core
material in a sintering oven; operate the sintering oven to sinter
the compacted powder metal and the embedded core material to form a
sintered powder metal part with the embedded core material
remaining embedded therein throughout the sintering process to
maintain the definition of the transverse feature; position the
sintered powder metal part with the embedded core material in a
forging apparatus; operate the forging apparatus to forge the
sintered powder metal part and the embedded core material to form a
forged powder metal part with the embedded core material remaining
embedded therein throughout the forging process to maintain the
definition of the transverse feature; remove the embedded core
material from the forged powder metal part to expose the transverse
feature therein.
[0025] It is noted that recitations herein of a component of an
embodiment being "configured" in a particular way or to embody a
particular property, or function in a particular manner, are
structural recitations as opposed to recitations of intended use.
More specifically, the references herein to the manner in which a
component is "configured" denotes an existing physical condition of
the component and, as such, is to be taken as a definite recitation
of the structural factors of the component.
[0026] It is noted that terms like "generally," "commonly," and
"typically," when utilized herein, are not utilized to limit the
scope of the claimed embodiments or to imply that certain features
are critical, essential, or even important to the structure or
function of the claimed embodiments. Rather, these terms are merely
intended to identify particular aspects of an embodiment or to
emphasize alternative or additional features that may or may not be
utilized in a particular embodiment.
[0027] For the purposes of describing and defining embodiments
herein it is noted that the terms "substantially," "significantly,"
and "approximately" are utilized herein to represent the inherent
degree of uncertainty that may be attributed to any quantitative
comparison, value, measurement, or other representation. The terms
"substantially," "significantly," and "approximately" are also
utilized herein to represent the degree by which a quantitative
representation may vary from a stated reference without resulting
in a change in the basic function of the subject matter at
issue.
[0028] Having described embodiments of the present invention in
detail, and by reference to specific embodiments thereof, it will
be apparent that modifications and variations are possible without
departing from the scope of the embodiments defined in the appended
claims. More specifically, although some aspects of embodiments of
the present invention are identified herein as preferred or
particularly advantageous, it is contemplated that the embodiments
of the present invention are not necessarily limited to these
preferred aspects.
* * * * *