Detailed Office Action
Notice of Pre-AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA
Response to Amendments
The amendment filed on 03/13/2026 has been entered. Claims 1 – 4 have been canceled. Claims 21 – 24 are newly added and find support at least [0039, 0050] and the original claim set.
Applicant’s amendments have overcome the previous objections and rejections under 112(b). Said rejections are withdrawn.
Claim Interpretation
Aapplicant has not defined or provided a clear indication of the what the basic and novel characteristics are and as such, the phrase “consisting essentially of” is interpreted as open (i.e. “comprising”). “The transitional phrase "consisting essentially of" limits the scope of a claim to the specified materials or steps "and those that do not materially affect the basic and novel characteristic(s)" of the claimed invention. In re Herz, 537 F.2d 549, 551-52, 190 USPQ 461, 463 (CCPA 1976) (emphasis in original). For the purposes of searching for and applying prior art under 35 U.S.C. 102 and 103, absent a clear indication in the specification or claims of what the basic and novel characteristics actually are, "consisting essentially of" will be construed as equivalent to "comprising." See, e.g., PPG, 156 F.3d at 1355, 48 USPQ2d at 1355 ("PPG could have defined the scope of the phrase ‘consisting essentially of’ for purposes of its patent by making clear in its specification what it regarded as constituting a material change in the basic and novel characteristics of the invention.").” (MPEP 2111.03 III)
Claim Rejections – U.S.C. §103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 5 – 8 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013)
Regarding claim 5 and 11, Xu teaches a method of producing a steel part [0002]. Xu teaches the steel has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.1%
trace to 0.4%
Overlaps
Nickel (Ni)
4.5 – 8.5%
2 – 7.5%
Overlaps
Chromium (Cr)
5.5 – 9.5%
7 – 11%
Overlaps
Molybdenum (Mo)
4.5 – 7.5%
4 – 7%
Overlaps
Cobalt (Co)
13.0 – 18.0%
6 – 15%
Overlaps
Vanadium (V)
≤ 1.0%
≤ 1% [0034]
Falls within
Iron (Fe)
Balance/remaining
50 – 80%
Meets
*Wherein the examiner notes that, as discussed above, the applicant has not defined or provided a clear indication of the what the basic and novel characteristics are and as such, the phrase is interpreted as open (i.e. “comprising”). Xu meets this claimed composition limitation.
Xu teaches that the steel part is made by a method of:
Mixing the steel powder with a binder [0062] and pelleting [0063], the binder can be a polymer [0071]
Meeting the claimed limitation of preparing an alloy material powder, mixing the powder and a polymer binder, and obtaining a feed
Forming the steel part via metal injection molding [0067]
Meeting the claimed limitation of pouring feed into an injection molding machine.
Performing degreasing to remove binder [0069]
Meeting the claimed limitation of performing degreasing on the green body to remove the polymer binder
Sintering the degreased green body [0170]
Performing sintering using a sintering device to obtain a sintered product
Performing a solid solution treatment and aging treatment [0177].
Meeting the claimed limitation of performing solution treatment and aging.
Xu teaches that the yield strength of the formed component is 2000 MPa or less [0015], which overlaps with the claimed range.
Xu does not expressly teach the yield strength of the sintered component prior to heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu teaches a substantially identical method of mixing, injection molding, degreasing, and sintering. As such, there is a reasonable expectation to an ordinarily skilled artisan that the sintered component of Xu would possess the claimed yield strength.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Xu does not explicitly teach that shaping is performed postsintering. Xu does not teach applying a cryogenic treatment to the component.
Bose provides information regarding the metal injection molding process [Title]. Bose describes that postsinter operations are common in metal injection molding processes [page 20, right column, “Post Sinter Secondary Operations”]. Moreover, Bose teaches that various postsinter secondary operations can be carried out in order to meet dimensional specifications and these include machining and coining [page 21, left column], meeting the claimed limitation of cold (room temperature) shaping of claim 11.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and included a postsinter machining and/or coining operation, as disclosed by Bose, to achieve predictable results. Xu is directed to a metal injection molding process and Bose provides additional information about this type of process. As such, an ordinarily skilled artisan would have considered the teachings of Bose to be pertinent to Xu and would have had a reasonable expectation of success in applying the teachings the method of Xu. Moreover, as disclosed by Bose, postsinter secondary operations of machining and/or coining are beneficial for meeting dimensional specifications, a benefit an ordinarily skilled artisan would appreciate as benefiting Xu when needing to ensure tolerances and meeting particular dimensional specifications.
Xu does not expressly teach the yield strength of the sintered component prior to heat treatment. Xu does not teach applying a cryogenic treatment to the component.
Sato teaches a method of producing a precipitation-strengthened steel [0001], which contains a similar composition to Xu [0006], that is subjected to a heat treatment to produce a martensitic structure and precipitation strengthening [0014]. Additionally, Sato teaches that following the solution treatment, a subzero treatment can be performed in a temperature range of -50 to -100°C for a time of 0.5 – 3 hours [0015], which overlaps with the claimed ranges. Sato teaches that the sub-zero treatment allows for reducing the amount of retained austenite and thereby improve mechanical properties such as yield strength [0015]. Moreover, as discussed by Diekman (NPL)(providing information about cold treatment of steels), cold treatment increases strength, improves dimensional and microstructural stability, and relieves residual stress [page 1, “cold treatment of steel”].
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have modified the method of Xu to have a subzero treatment in the time and temperature range described by Sato. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have a reasonable expectation of success in applying the subzero treatment of Sato to the method of Xu. Further still, Sato discloses that the subzero treatment reduces the amount of retained austenite to thereby improve mechanical properties such as yield strength and Diekman (NPL) teaches that cold treatment can provide various benefits including increasing strength, improving dimensional and microstructural stability, and relieving residual stresses. As such, an ordinarily skilled artisan would have had motivation to apply a subzero treatment to attain the various benefits disclosed in the prior art.
With regards to the overlapping ranges taught, it would have been obvious to an ordinarily skilled artisan before the effective filing date of the claimed invention to have selected overlapping ranges as disclosed. Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Regarding claim 6, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 5. Xu teaches that the d50 grain size is 5 – 15 µm, which falls within the claimed range [0136]. Xu does not explicitly teach the tap density, however, given that the Xu teaches an overlapping composition and d50 powder size, an ordinarily skilled artisan would expect that Xu would meet/overlap the claimed tap density.
The USPTO does not possess the capability to test samples of the prior art to determine the properties/microstructure as claimed. As such, given the overlapping composition and substantially identical d50 grain size, the burden is shifted to applicant to demonstrate that the prior art does not possess such feature(s) (i.e. tap density) (In re Fitzgerald, 619 F.2d 67, 205 USPQ 594 (CCPA 1980)). Moreover, Selection of overlapping ranges has been held to be a prima facie case of obviousness, absent evidence of criticality (See MPEP § 2144.05 I).
Regarding claims 7 – 8, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 5. Xu teaches that the steel powder to binder ratio depends on the actual requirements needed and can be determined/selected by a person of ordinary skill in the art [0152]. Xu explicitly teaches an example in which the steel powder to binder volume ratio is 62:38 (1.63:1), which falls within the claimed range of claims 7 and 8. Said example also includes mixing at 170 – 210°C, which falls within the claimed range of 7 and 8, for 2 – 4 hr, which falls within the claimed range of 7 and 8 [0152].
Xu does not explicitly teach the type of mixer used.
Bose provides information regarding mixing of the powder binder blend [Page 7, middle column]. The Bose states that Z-blade (i.e. sigma-type) mixers are used in the production of the feedstock [Page 7, middle column].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and used a z-blade mixer, as disclosed by Bose, to achieve predictable results. Xu is directed to a metal injection molding process and Bose provides additional information about this type of process. As such, an ordinarily skilled artisan would have a reasonable expectation of success in applying the teachings of Bose to the method of Xu. Moreover, as disclosed by Bose the z-blade mixers/mixing is used in creating feedstock for metal injection molding. As such, the combination would achieve predictable results and would not change their respective functions.
The combination of prior art elements to yield predictable results is a prima facie case of obviousness (See MPEP 2143 A). “The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art”. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976)
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 5, in further view of Nakamura (US2018/0009031, cited with the OA on 9/29/25)
Regarding claim 6, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 5. Xu teaches that the d50 grain size is 5 – 15 µm, which falls within the claimed range [0136]. Xu does not explicitly teach the tap density.
Nakamura teaches a forming a body by injection molding [0190]. Nakamura teaches a similar alloy to Xu and the claimed invention of C 0.005-0.3 mass% [0035] Ni 5 – 20 mass% [0040], Cr 9 – 15 mass% [0058], Mo 0.1 – 6 mass% [0070], Co 6 – 14 mass% [0064], vanadium as a first element in a range of 0.01 – 0.7 [0035], and iron as the principal component [Abstract]. Nakamura teaches that the powder composition should have a tap density of 4.0 g/cm3 or more [0162], which overlaps with the claimed range. Nakamura states that higher tap density increases interparticle packing efficiency after molding and thus obtains a particularly dense sintered body [0162].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and controlled the tap density of the metal powder to be 4.0 g/cm3 or more, as disclosed by Nakamura. Xu and Nakamura are directed to metal injection molding of similar alloy compositions and as such, an ordinarily skilled artisan would have considered the teachings of Nakamura to be reasonably pertinent to the method of Xu and would have had a reasonable expectation of success in applying said teachings. Moreover, as disclosed by Nakamura the greater the tap density of the powder the greater the interparticle packing efficiency, which leads to a denser sintered component. As such, it would have been obvious to an ordinarily skilled artisan to have maximized the tap density of the metal powder of Xu, to ultimately achieve a denser final component.
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”. Additionally, the routine optimization of a result effective variable is a prima facie case of obviousness (MPEP 2144.05 II). In this case, it would have been routine optimization to arrive at the claimed density because Xu teaches an overlapping composition and D50 grain size that falls within the claimed range, and Nakamura teaches that tap density should be at least 4.0 g/cm3 but maximizing it would greater a denser sintered product.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 5, in further view of Ge (CN113969378, using espacenet translation)
Regarding claim 9, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 5. Xu teaches that degreasing can involve catalytic degreasing in a furnace and that the time, temperature, and atmosphere are not particularly limited and may be selected based on requirement/desire of an ordinarily skilled artisan [0169].
Xu teaches a particular example in which the temperature is 110 – 130°C, which falls within the claimed range, for 2 – 4 hr, which falls within the claimed range, using nitric acid, meeting the claimed limitation [0169].
Xu does not expressly teach that the specific atmosphere selected is nitrogen.
Ge teaches producing a steel alloy by injection molding, degreasing, sintering and heat – treating [0012, 0013]. Ge teaches a similar alloy to Xu and the claimed invention of C less than 0.03 mass%, Ni 6 – 10 mass%, Cr 9 – 12 mass%, Mo 6 – 10 mass%, and Co 8 – 12 mass%, and iron as balance [0007]. Ge teaches that catalytic degreasing is also employed using nitric acid and that during degreasing nitrogen is used as a protective gas and oxygen is minimized [0081]
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and controlled the specific atmosphere of degreasing to be nitrogen, as disclosed by Ge. Xu and Ge are directed to metal injection molding of similar alloy compositions and as such, an ordinarily skilled artisan would have considered the teachings of Ge to be reasonably pertinent to the method of Xu and would have had a reasonable expectation of success in applying said teachings. Moreover, as disclosed by Ge the use of nitrogen and minimizing oxygen forms a protective atmosphere and an ordinarily skilled artisan would understand that said atmosphere would reduce the potential for oxidation during degreasing.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 5, in further view of Xu (CN113560576, using espacenet translation, and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24)
Regarding claim 10, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 5. Xu teaches sintering at 1200 – 1400°C, which falls within the claimed range, for 1.5 – 4 hr, which overlaps with the claimed range, in an argon atmosphere [0171].
However, Xu does not explicitly teach a thermal degreasing step or the partial pressure of argon in the sintering atmosphere. Xu does note that specific sintering conditions are based on need [0171].
Bose states that it is not technically sound to use a one component binder system because it causes the green part to lose shape during debinding [page 14, right column, “debinding”]. Bose teaches that instead, a multicomponent binder system is often used and that the debinding is conducted in two phases with the first phase being by chemical or thermal means and the second phase being conducted by thermal means, in order to remove the remaining binder [Page 15, left column]. Wherein the first phase can be catalytic debinding [page 15, center col, top]. Bose does not expressly teach thermal degreasing conditions.
CN ‘576 teaches a method of making a high-strength, high-toughness steel component via mixing, injection molding, degreasing, sintering, and solution treatment and aging [0005, 0008 – 0011]. CN ‘576 teaches using a multicomponent binder system [0035] that is first removed by catalytic debinding to remove most of the binder, and then completely removed by a second thermal-based debinding step [0034]. CN ‘576 states that the temperature used is lower than the sintering temperature in order to remove the remaining binder without causing it to decompose into carbon and/or oxygen [0034]. CN’576 teaches that thermal treatment includes the step of heating 500 – 800°C and holding for 0 – 180 min [0024], which overlaps with the claimed range. Additionally, CN ‘576 teaches sintering in a similar temperature and time range under an inert gas atmosphere, wherein the inert gas pressure is 0 – 100 kPa, which overlaps with the claimed range and meets the limitation of vacuum [0026].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and added a thermal degreasing step with a temperature of 500 – 800°C and a holding time of 0 – 180 min following catalytic degreasing, as disclosed by CN ‘576. Xu, Bose, and CN ‘576 are directed to metal injection molding of similar alloy compositions and as such, an ordinarily skilled artisan would have considered the teachings of Bose and CN ‘576 to be reasonably pertinent to the method of Xu and would have had a reasonable expectation of success in applying said teachings. Moreover, as disclosed by Bose using two step debinding allows for slower and more complete removal of a multicomponent binder (wherein Xu teaches a multicomponent binder [0071, 0155]) such that the green part successfully retains its shape. CN ‘576 also teaches that thermal degreasing below the sintering temperature prevents the binder from breaking down into carbon and oxygen. As such, an ordinarily skilled artisan would have been motivated to have applied an additional thermal degreasing step in the temperature and time disclosed by CN ‘576.
Moreover, it would have been obvious to one of ordinary skill in the art before the effective filing date to have used the inert gas pressure range of 0 – 100 kPa, which overlaps with the claimed range, as the sintering pressure in the sintering step of Xu to achieve predictable results. Both Xu and CN ‘576 are directed to sintering steel alloys in an inert gas atmosphere after injection molding and as such, an ordinarily skilled artisan would have had a reasonable expectation of success in applying the teachings with no change in their respective functions.
The combination of prior art elements to yield predictable results is a prima facie case of obviousness (See MPEP 2143 A). Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I).
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Claims 12 – 13 and 15 – 19 are rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), Xu (CN113560576, using espacenet translation and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24), and Heuer (ASM Handbook, “Gas Quenching”, 2013).
Regarding claims 12 – 13 and 15, Xu teaches a method of producing a steel part [0002]. Xu teaches the steel has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.1%
trace to 0.4%
Overlaps
Nickel (Ni)
4.5 – 8.5%
2 – 7.5%
Overlaps
Chromium (Cr)
5.5 – 9.5%
7 – 11%
Overlaps
Molybdenum (Mo)
4.5 – 7.5%
4 – 7%
Overlaps
Cobalt (Co)
13.0 – 18.0%
6 – 15%
Overlaps
Vanadium (V)
≤ 1.0%
≤ 1% [0034]
Falls within
Iron (Fe)
Balance/remaining
50 – 80%
Meets
*Wherein the examiner notes that, as discussed above, the applicant has not defined or provided a clear indication of the what the basic and novel characteristics are and as such, the phrase is interpreted as open (i.e. “comprising”). Xu meets this claimed composition limitation.
Xu teaches that the steel part is made by a method of:
Mixing the steel powder with a binder [0062] and pelleting [0063], the binder can be a polymer [0071]
Meeting the claimed limitation of preparing an alloy material powder, mixing the powder and a polymer binder, and obtaining a feed
Forming the steel part via metal injection molding [0067]
Meeting the claimed limitation of pouring feed into an injection molding machine.
Performing degreasing to remove binder [0069]
Meeting the claimed limitation of performing degreasing on the green body to remove the polymer binder
Sintering the degreased green body [0170]
Performing sintering using a sintering device to obtain a sintered product
Performing a solid solution treatment and aging treatment [0177].
Meeting the claimed limitation of performing solution treatment and aging.
Xu teaches that the yield strength of the formed component is 2000 MPa or less [0015], which overlaps with the claimed range.
Xu does not expressly teach the hardness or yield strength of the sintered component prior to heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu teaches a substantially identical method of mixing, injection molding, degreasing, and sintering. As such, there is a reasonable expectation to an ordinarily skilled artisan that the sintered component of Xu would possess the claimed yield strength.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Xu does not explicitly teach that shaping is performed postsintering. Xu does not expressly teach the details of the heat treatment (solutionizing and aging). Xu does not teach applying a cryogenic treatment to the component.
Bose provides information regarding the metal injection molding process [Title]. Bose describes that postsinter operations are common in metal injection molding processes [page 20, right column, “Post Sinter Secondary Operations”]. Moreover, Bose teaches that various postsinter secondary operations can be carried out in order to meet dimensional specifications and these include machining and coining [page 21, left column].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and included a postsinter machining and/or coining operation, as disclosed by Bose, to achieve predictable results. Xu is directed to a metal injection molding process and Bose provides additional information about this type of process. As such, an ordinarily skilled artisan would have a reasonable expectation of success in applying the teachings of Bose to the method of Xu. Moreover, as disclosed by Bose, postsinter secondary operations of machining and/or coining are beneficial for meeting dimensional specifications, a benefit an ordinarily skilled artisan would appreciate as benefiting Xu when needing to ensure tolerances and meeting particular dimensional specifications.
Xu does not expressly teach the details of the heat treatment (solutionizing and aging). Xu does not teach applying a cryogenic treatment to the component.
Sato teaches a method of producing a precipitation-strengthened steel [0001], which contains a similar composition to Xu [0006], that is subjected to a heat treatment to produce a martensitic structure and precipitation strengthening [0014]. The heat treatment includes solution treatment, sub-zero treatment, and aging, meeting claim 15.
Sato teaches that the solution treatment is conducted at a temperature range of 850 – 1050°C for 0.5 – 3 hours (which falls within the claimed range), and that cooling is conducted by cooling gas to room temperature [0014, 0015]. Sato teaches that the aging treatment is conducted in a temperature range of 500 – 600°C, which falls within the claimed range, for 1 – 24 hours, which overlaps with the claimed range [0015]. Sato teaches that the time and temperature conditions are desirable for obtaining sufficient dissolution of alloy elements (and therefore sufficient precipitation in the subsequent aging treatment) without causing the crystal grains or precipitates to become too coarse [0015].
Lastly, Sato teaches that following the solution treatment, a subzero treatment can be performed in a temperature range of -50 to -100°C for a time of 0.5 – 3 hours [0015], which overlaps with the claimed ranges of claim 13. Sato teaches that the sub-zero treatment allows for reducing the amount of retained austenite and thereby improve mechanical properties such as yield strength [0015]. Moreover, as discussed by Diekman (NPL)(providing information about cold treatment of steels), cold treatment increases strength, improves dimensional and microstructural stability, and relieves residual stress [page 1, “cold treatment of steel”].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied the solution treatment and aging conditions disclosed by Sato to the solution treatment and aging in Xu to achieve predictable results. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have considered Sato pertinent to the invention of Xu and would have had a reasonable expectation of success in applying the solution treatment conditions of Sato to the method of Xu. Moreover, Sato discloses that the solution treatment conditions obtain sufficient dissolution of alloy elements (and therefore sufficient precipitation in the subsequent aging treatment) without causing the crystal grains to become too coarse and that the solutionizing and subsequent aging provides high strength without allowing the precipitants to become excessively coarse. Therefore, an ordinarily skilled artisan would have been motivated to apply the teachings of the heat treatment of Sato to Xu.
Additionally, it would have been obvious to one of ordinary skill in the art before the effective filing date to have modified the method of Xu to have a subzero treatment in the time and temperature range described by Sato. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have considered Sato pertinent to the invention of Xu and would have had a reasonable expectation of success in applying the subzero treatment of Sato to the method of Xu. Sato discloses that the subzero treatment reduces the amount of retained austenite to thereby improve mechanical properties such as yield strength and Diekman (NPL) teaches that cold treatment can provide various benefits including increasing strength, improving dimensional and microstructural stability, and relieving residual stresses. As such, an ordinarily skilled artisan would have had motivation to apply a subzero treatment to attain the various benefits disclosed in the prior art.
Xu in view of Bose, Sato, and Diekman does not explicitly teach that the solutionizing and aging treatment is conducted under vacuum.
CN ‘576 teaches a method of making a high-strength, high-toughness steel component via mixing, injection molding, degreasing, sintering, and solution treatment and aging [0005, 0008 – 0011]. CN ‘576 teaches performing a solution and aging treatment to achieve precipitation hardening and martensitic formation [0038, 0039]. In particular, CN ‘576 teaches that the solutionizing and aging treatment can be conducted under vacuum [0037, 0038].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have used a vacuum atmosphere in the solutionizing and aging treatment in Xu as-modified to achieve predictable results. Xu, Sato, and CN ‘576 are directed to producing steel to which precipitation strengthening and martensitic formation are conducted, including solutionizing and aging. As such, an ordinarily skilled artisan would have considered the teachings of CN ‘576 to be pertinent to Xu and would have had a reasonable expectation of success in using a vacuum atmosphere in the solutionizing and aging treatment of Xu as-modified. Moreover, a person possessing ordinary skill in the art would reasonably understand that vacuum atmospheres are known for being protective from impurities/oxidation during heat treatment and as such, would be motivated to apply vacuum to prevent this. This is evidenced by Xu, which explicitly notes vacuum as a protective atmosphere [0171].
Xu in view of Bose, Sato, Diekman, and CN ‘576 does not teach the gas or pressure of said gas that is used for gas cooling following solution treatment [Sato, 0014].
Heuer teaches information regarding gas quenching for steel heat treating [Title]. Heuer teaches that gas quenching is often performed with an inert gas flow at a pressure of 1 – 20 bar, which overlaps with the claimed range, in order to convert austenite to martensite [Introduction], wherein inert gas includes argon (i.e. an inert gas) as well as nitrogen [Table 2]. Heuer also teaches that gas quenching offers low distortion as compared to liquid quenching, cleaner parts, and control of quench intensity [Introduction].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied a pressure of 1 – 20 bar using inert gas (nitrogen and/or argon) to perform gas cooling following the solution treatment in the method of Xu as-modified, in order to help convert martensite. Heuer is directed to standards for performing gas cooling on steel products and as such, an ordinarily skilled artisan would have a reasonable expectation of success in applying the teachings and would have considered them pertinent. Moreover, Heuer teaches that gas cooling offers various benefits including low distortion as compared to liquid quenching, cleaner parts, and control of quench intensity [Introduction]. As such, an ordinarily skilled artisan would have been motivated to apply the conditions disclosed by Heuer to the method of Xu as-modified.
With regards to the overlapping ranges taught, it would have been obvious to an ordinarily skilled artisan before the effective filing date of the claimed invention to have selected overlapping ranges as disclosed. Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Lastly, Xu does not expressly teach the hardness of the final component after heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu as-modified teaches a substantially identical method of mixing, injection molding, degreasing, and sintering as well as solutionizing, treating at sub-zero temperatures, and aging. As such, there is a reasonable expectation to an ordinarily skilled artisan that the component of Xu as-modified would possess the claimed hardness.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Regarding claim 16, Xu in view of Bose, Sato, Diekman, CN ‘576, and Heuer teaches the invention as applied in claim 15. Sato teaches that the subzero treatment is performed in a temperature range of -50 to -100°C, which overlaps with the claimed temperature, for a time of 0.5 – 3 hours [0015], which lies outside the claimed time (4 hrs). However, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985) “The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.” (MPEP 2144.05 I). "Where the component elements of alloys are the same, and where they approach so closely the same range of quantities as is here the case, it seems that there ought to be some noticeable difference in the qualities of the respective alloys.". In this case, the upper bound of Sato of 3 hours is close to the claimed time of 4 hours such that an ordinarily skilled artisan would have expected them to result in the same properties.
Regarding claim 17, Xu in view of Bose, Sato, Diekman, CN ‘576, and Heuer teaches the invention as applied in claim 15. Xu teaches the method has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.02%
trace to 0.4%
Overlaps
Nickel (Ni)
5.5 – 6.5%
2 – 7.5%
Overlaps
Chromium (Cr)
8.5 – 9.5%
7 – 11%
Overlaps
Molybdenum (Mo)
5.5 – 6.5%
4 – 7%
Overlaps
Cobalt (Co)
14.5 – 15.5%
6 – 15%
Overlaps
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I)
Regarding claim 18, Xu in view of Bose, Sato, Diekman, CN ‘576, and Heuer teaches the invention as applied in claim 15. Xu teaches the method has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.08%
trace to 0.4%
Overlaps
Nickel (Ni)
4.5 – 5.5%
2 – 7.5%
Overlaps
Chromium (Cr)
7.5 – 8.5%
7 – 11%
Overlaps
Molybdenum (Mo)
4.5 – 5.5%
4 – 7%
Overlaps
Cobalt (Co)
13.0 – 13.5%
6 – 15%
Overlaps
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I)
Regarding claim 19, Xu in view of Bose, Sato, Diekman, CN ‘576, and Heuer teaches the invention as applied in claim 15. Xu teaches the method has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.08%
trace to 0.4%
Overlaps
Nickel (Ni)
6.5 – 7.5%
2 – 7.5%
Overlaps
Chromium (Cr)
8.5 – 9.5%
7 – 11%
Overlaps
Molybdenum (Mo)
6.5 – 7.5%
4 – 7%
Overlaps
Cobalt (Co)
15.5 – 16.5%
6 – 15%
Outside of
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). Moreover, in regards to the content of cobalt, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985) “The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.” (MPEP 2144.05 I). "Where the component elements of alloys are the same, and where they approach so closely the same range of quantities as is here the case, it seems that there ought to be some noticeable difference in the qualities of the respective alloys.".
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), Xu (CN113560576, using espacenet translation and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24), and Heuer (ASM Handbook, “Gas Quenching”, 2013), as applied to claim 12, in further view of Thomas (NPL, “Pit Furnace”, 2019)
Regarding claim 14, Xu in view of Bose, Sato, Diekman, CN ‘576, and Heuer teaches the invention as applied in claim 12. Sato teaches that the aging treatment is conducted in a temperature range of 500 – 600°C for 1 – 24 hours [0015], which overlaps with the claimed ranges. Wherein lowering the temperature of component after aging is implied.
While Xu as-modified does not expressly teach the heating rate. The heating rate of the components would be determined based on the furnace type (e.g., gas, induction) being used as well as the type/size of the component being produced (e.g., larger components vs smaller components). As such, it would have been routine experimentation to have determined/discovered the heating rate based upon the furnace used and the size/type of the component to be made. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). (MPEP 2114.05 II A)
Absent evidence of criticality, unexpected results, or other secondary considerations, a determining/discovering of workable ranges by routine experimentation is a prima facie case of obviousness. Applicants can rebut a prima facie case of obviousness by showing the criticality of the range. "The law is replete with cases in which the difference between the claimed invention and the prior art is some range or other variable within the claims. . . . In such a situation, the applicant must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results relative to the prior art range." In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). ("Where the issue of criticality is involved, the applicant has the burden of establishing his position by a proper showing of the facts upon which he relies."); In re Becket, 88 F.2d 684 (CCPA 1937) (MPEP 2114.05 III A)
Xu as-modified discloses using gas/air as the cooling medium [Sato, 0014; CN ‘576, 0051] in the heat treatment furnace but does not expressly state the furnace has a fan.
Thomas teaches information regarding pit furnaces [Title]. Thomas teaches that when, for example, hardening and/or annealing is performed, the furnace has a mounted fan to maintain temperature uniformity throughout the furnace [page 7].
As such, it would have been obvious to one of ordinary skill in the art before the effective filing date to have ensured a fan was present and on during heat treatment steps of Xu as-modified in order to ensure temperature uniformity, as taught by Thomas. Given that Thomas is directed to heat treatment furnaces, an ordinarily skilled artisan would have considered the teachings pertinent to Xu and would have had a reasonable expectation of success in applying them. Additionally, an ordinarily skilled artisan would have been motivated to apply the teachings because Thomas teaches that fans provide better temperature uniformity in the furnace.
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013)
Regarding claim 20, Xu teaches a method of producing a steel part [0002]. Xu teaches the steel has a composition of [0006]:
Element
Claimed Composition (wt%)
Xu (mass)
Relationship
Carbon (C)
≤ 0.1%
trace to 0.4%
Overlaps
Nickel (Ni)
4.5 – 5.5%
2 – 7.5%
Overlaps
Chromium (Cr)
7.5 – 8.5%
7 – 11%
Overlaps
Molybdenum (Mo)
4.5 – 5.5%
4 – 7%
Overlaps
Cobalt (Co)
13.0 – 13.5%
6 – 15%
Overlaps
Silicon (Si)
Trace amounts
Trace to 0.5%
Overlaps
Iron (Fe)
Balance/remaining
50 – 80%
Meets
Xu teaches that the steel part is made by a method of:
Mixing the steel powder with a binder [0062] and pelleting [0063], the binder can be a polymer [0071]
Meeting the claimed limitation of preparing an alloy material powder, mixing the powder and a polymer binder, and obtaining a feed.
Forming the steel part via metal injection molding [0067]
Meeting the claimed limitation of pouring feed into an injection molding machine to form a green body.
Performing degreasing to remove binder [0069]
Meeting the claimed limitation of performing degreasing on the green body to remove the polymer binder
Sintering the degreased green body [0170]
Performing sintering using a sintering device to obtain a sintered product.
Performing a solid solution treatment and aging treatment [0177].
Meeting the claimed limitation of performing heat treatment.
Xu teaches that the yield strength of the formed component is 2000 MPa or less [0015], which overlaps with the claimed range.
Xu does not expressly teach the hardness or yield strength of the sintered component prior to heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu teaches a substantially identical method of mixing, injection molding, degreasing, and sintering. As such, there is a reasonable expectation to an ordinarily skilled artisan that the sintered component of Xu would possess the claimed yield strength.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Xu does not explicitly teach that shaping is performed postsintering. Xu does not teach applying a cryogenic treatment to the component between solutionizing and aging.
Bose provides information regarding the metal injection molding process [Title]. Bose describes that postsinter operations are common in metal injection molding processes [page 20, right column, “Post Sinter Secondary Operations”]. Moreover, Bose states that various postsinter secondary operations can be carried out in order to meet dimensional specifications and these include machining and coining [page 21, left column].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and included a postsinter machining and/or coining operation, as disclosed by Bose, to achieve predictable results. Xu is directed to a metal injection molding process and Bose provides additional information about this type of process. As such, an ordinarily skilled artisan would have considered the teachings of Bose to be pertinent to Xu and would have had a reasonable expectation of success in applying the teachings of Bose to Xu. Moreover, as disclosed by Bose the postsinter secondary operations of machining and/or coining are beneficial for meeting dimensional specifications, a benefit an ordinarily skilled artisan would appreciate as benefiting Xu when needing to ensure tolerances and meeting particular dimensional specifications.
Xu as-modified does not teach applying a cryogenic treatment to the component between solutionizing and aging.
Sato teaches a method of producing a precipitation-strengthened steel [0001], which contains a similar composition to Xu [0006], that is subjected to a heat treatment to produce a martensitic structure and precipitation strengthening [0014]. Additionally, Sato teaches that following the solution treatment, a subzero treatment can be performed in a temperature range of -50 to -100°C for a time of 0.5 – 3 hours [0015], which overlaps with the claimed ranges. Sato teaches that the sub-zero treatment allows for reducing the amount of retained austenite and thereby improve mechanical properties such as yield strength [0015]. Moreover, as discussed by Diekman (NPL)(providing information about cold treatment of steels), cold treatment increases strength, improves dimensional and microstructural stability, and relieves residual stress [page 1, “cold treatment of steel”].
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have modified the method of Xu to have a subzero treatment in the time and temperature range described by Sato. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have considered the teachings of Sato to be pertinent to Xu and would have had a reasonable expectation of success in applying the subzero treatment to the method of Xu. Further still, Sato discloses that the subzero treatment reduces the amount of retained austenite to thereby improve mechanical properties such as yield strength and Diekman (NPL) teaches that cold treatment can provide various benefits including increasing strength, improving dimensional and microstructural stability, and relieving residual stresses. As such, an ordinarily skilled artisan would have had motivation to apply a subzero treatment to attain the various benefits disclosed in the prior art.
With regards to the overlapping ranges taught, it would have been obvious to an ordinarily skilled artisan before the effective filing date of the claimed invention to have selected overlapping ranges as disclosed. Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Lastly, Xu does not expressly teach the hardness of the final component after heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu as-modified teaches a substantially identical method of mixing, injection molding, degreasing, and sintering as well as solutionizing, treating at sub-zero temperatures, and aging. As such, there is a reasonable expectation to an ordinarily skilled artisan that the component of Xu as-modified would possess the claimed hardness.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Claim 21 rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 20, in further view of Xu (CN113560576, using espacenet translation, and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24) and Heuer (ASM Handbook, “Gas Quenching”, 2013).
Regarding claim 21, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 20. Xu teaches performing solution treatment and aging but does not explicitly teach the conditions used [0176, 0177].
Sato teaches a method of producing a precipitation-strengthened steel [0001], which contains a similar composition to Xu [0006], that is subjected to a heat treatment to produce a martensitic structure and precipitation strengthening [0014]. The heat treatment includes solution treatment and aging [0014]. In particular, Sato teaches that the solution treatment is conducted at a temperature range of 850 – 1050°C for 0.5 – 3 hours, which falls within the claimed ranges, and that cooling is conducted by cooling gas to room temperature [0014, 0015], meets/falls within the claimed cooling temperature. Sato teaches that the time and temperature conditions are desirable for obtaining sufficient dissolution of alloy elements (and therefore sufficient precipitation in the subsequent aging treatment) without causing the crystal grains to become too coarse [0014].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied the solution treatment conditions disclosed by Sato to the solution treatment in Xu to achieve predictable results. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have considered the teachings of Sato pertinent to Xu and would have had a reasonable expectation of success in applying the solution treatment conditions of Sato to the method of Xu. Moreover, Sato discloses that the solution treatment conditions obtain sufficient dissolution of alloy elements (and therefore sufficient precipitation in the subsequent aging treatment) without causing the crystal grains to become too coarse, thereby providing a benefit that an ordinarily skilled artisan would appreciate.
Xu in view of Bose, Sato, and Diekman does not explicitly teach that the solutionizing treatment is conducted under vacuum.
CN ‘576 teaches a method of making a high-strength, high-toughness steel component via mixing, injection molding, degreasing, sintering, and solution treatment and aging [0005, 0008 – 0011]. CN ‘576 teaches performing a solution and aging treatment to achieve precipitation hardening and martensitic formation [0038, 0039]. In particular, CN ‘576 teaches that the solutionizing and aging treatment can be conducted under vacuum [0037, 0038].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have used a vacuum atmosphere in the solutionizing treatment in Xu as-modified to achieve predictable results. Xu, Sato, and CN ‘576 are directed to producing steel to which precipitation strengthening and martensitic formation are conducted, including solutionizing and aging. As such, an ordinarily skilled artisan would have considered the teachings of CN ‘576 to be pertinent to Xu and would have had a reasonable expectation of success in using a vacuum atmosphere in the solutionizing treatment of Xu as-modified. Moreover, a person possessing ordinary skill in the art would reasonably understand that vacuum atmospheres are known for being protective from impurities/oxidation during heat treatment and as such, would be motivated to apply vacuum to prevent this. This is evidenced by Xu, which explicitly notes vacuum as a protective atmosphere [0171].
Xu in view of Bose, Sato, Diekman, and CN ‘576 does not teach the gas or pressure of said gas that is used for gas cooling following solution treatment.
Heuer teaches information regarding gas quenching for steel heat treating [Title]. Heuer teaches that gas quenching is often performed with an inert gas flow at a pressure of 1 – 20 bar, which overlaps with the claimed range, in order to convert austenite to martensite [Introduction], wherein inert gas includes argon (i.e. an inert gas) as well as nitrogen [Table 2]. Heuer also teaches that gas quenching offers low distortion as compared to liquid quenching, cleaner parts, and control of quench intensity [Introduction].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied a pressure of 1 – 20 bar using inert gas (nitrogen and/or argon) to perform gas cooling following the solution treatment in the method of Xu as-modified, in order to help convert martensite. Heuer is directed to standards for performing gas cooling on steel products and as such, an ordinarily skilled artisan would have considered the teachings of Heuer to be pertinent to Xu and would have had a reasonable expectation of success in applying the teachings. Moreover, Heuer teaches that gas cooling offers various benefits including low distortion as compared to liquid quenching, cleaner parts, and control of quench intensity [Introduction]. As such, an ordinarily skilled artisan would have been motivated to apply the conditions disclosed by Heuer to the method of Xu.
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Claim 22 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 20, in further view of Xu (CN113560576, using espacenet translation, and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24).
Regarding claim 22, Xu in view of Bose, Sato and Diekman teaches the invention as applied in claim 20. Xu teaches performing solution treatment and aging but does not explicitly teach the conditions used [0176, 0177].
Sato teaches a method of producing a precipitation-strengthened steel [0001], which contains a similar composition to Xu [0006] that is subjected to a heat treatment to produce a martensitic structure and precipitation strengthening [0014]. The heat treatment includes solution treatment and aging [0014]. In particular, Sato teaches that the aging treatment is conducted in a temperature range of 500 – 600°C for 1 – 24 hours [0015], which overlaps with the claimed ranges, in order to obtain sufficient strength without creating excessively coarse precipitates [0015]. The lowering of the temperature after aging is implied in the method of Xu as well as Sato.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied the aging treatment conditions disclosed by Sato to the aging treatment in Xu to achieve predictable results. Sato and Xu are directed to producing steel with similar compositions and in which precipitation strengthening and martensitic formation are achieved. As such, an ordinarily skilled artisan would have had a reasonable expectation of success in applying the aging treatment conditions of Sato to the method of Xu. Moreover, Sato discloses that the heat treatment range provides high strength without allowing the precipitants to become excessively coarse thereby providing a benefit that an ordinarily skilled artisan would appreciate.
Xu in view of Bose and Sato does not explicitly teach that the aging treatment is conducted under vacuum.
CN ‘576 teaches a method of making a high-strength, high-toughness steel component via mixing, injection molding, degreasing, sintering, and solution treatment and aging [0005, 0008 – 0011]. CN ‘576 teaches performing a solution and aging treatment to achieve precipitation hardening and martensitic formation [0038, 0039]. In particular, CN ‘576 teaches that the aging treatment can be conducted under vacuum [0038].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have used a vacuum atmosphere in the aging treatment in Xu as-modified to achieve predictable results. Xu, Sato, and CN ‘576 are directed to producing steel to which precipitation strengthening and martensitic formation are conducted, including solutionizing and aging. As such, an ordinarily skilled artisan would have considered the teachings of CN ‘576 to be pertinent to Xu and would have had a reasonable expectation of success in using a vacuum atmosphere in the aging treatment of Xu as-modified. Moreover, a person possessing ordinary skill in the art would reasonably understand that vacuum atmospheres are known for being protective from impurities/oxidation during heat treatment and as such, would be motivated to apply vacuum to prevent this. This is evidenced by Xu, which explicitly notes vacuum as a protective atmosphere [0171].
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 20, in further view of Ge (CN113969378, using espacenet translation)
Regarding claim 23, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 20. Xu teaches that degreasing can involve catalytic degreasing in a furnace and that the time, temperature, and atmosphere are not particularly limited and may be selected based on requirement/desire of an ordinarily skilled artisan [0169].
Xu teaches a particular example in which the temperature is 110 – 130°C, which falls within the claimed range, for 2 – 4 hr, which falls within the claimed range, using nitric acid, meeting the claimed limitation [0169].
Xu does not expressly teach that the specific atmosphere selected is nitrogen.
Ge teaches producing a steel alloy by injection molding, degreasing, sintering and heat – treating [0012, 0013]. Ge teaches a similar alloy to Xu and the claimed invention of C less than 0.03 mass%, Ni 6 – 10 mass%, Cr 9 – 12 mass%, Mo 6 – 10 mass%, and Co 8 – 12 mass%, and iron as balance [0007]. Ge teaches that catalytic degreasing is also employed using nitric acid and that during degreasing nitrogen is used as a protective gas and oxygen is minimized [0081]
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and controlled the specific atmosphere of degreasing to be nitrogen, as disclosed by Ge. Xu and Ge are directed to metal injection molding of similar alloy compositions and as such, an ordinarily skilled artisan would have considered the teachings of Ge to be reasonably pertinent to the method of Xu and would have had a reasonable expectation of success in applying said teachings. Moreover, as disclosed by Ge the use of nitrogen and minimizing oxygen forms a protective atmosphere and an ordinarily skilled artisan would understand that said atmosphere would reduce the potential for oxidation during degreasing.
Claim 24 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721, cited in the IDS of 04/17/24) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869, using espacenet translation) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013), as applied to claim 20, in further view of Xu (CN113560576, using espacenet translation, and henceforth referred to as CN ‘576 for clarity, cited in the IDS of 04/17/24)
Regarding claim 24, Xu in view of Bose, Sato, and Diekman teaches the invention as applied in claim 20. Xu teaches sintering at 1200 – 1400°C, which falls within the claimed range, for 1.5 – 4 hr, which overlaps with the claimed range, in an argon atmosphere [0171].
Xu does not explicitly teach a thermal degreasing step or the partial pressure of argon in the sintering atmosphere. Xu does note that specific sintering conditions are based on need [0171].
Bose states that it is not technically sound to use a one component binder system because it causes the green part to lose shape during debinding [page 14, right column, “debinding”]. Bose teaches that instead, a multicomponent binder system is often used and that the debinding is conducted in two phases with the first phase being by chemical or thermal means and the second phase being conducted by thermal means, in order to remove the remaining binder [Page 15, left column]. Wherein the first phase can be catalytic debinding [page 15, center col, top]. Bose does not expressly teach thermal degreasing conditions.
CN ‘576 teaches a method of making a high-strength, high-toughness steel component via mixing, injection molding, degreasing, sintering, and solution treatment and aging [0005, 0008 – 0011]. CN ‘576 teaches using a multicomponent binder system [0035] that is first removed by catalytic debinding to remove most of the binder, and then completely removed by a second thermal-based debinding step [0034]. CN ‘576 states that the temperature used is lower than the sintering temperature in order to remove the remaining binder without causing it to decompose into carbon and/or oxygen [0034]. CN’576 teaches that thermal treatment includes the step of heating 500 – 800°C and holding for 0 – 180 min [0024], which overlaps with the claimed range. Additionally, CN ‘576 teaches sintering in a similar temperature and time range under an inert gas atmosphere, wherein the inert gas pressure is 0 – 100 kPa, which overlaps with the claimed range and meets the limitation of vacuum [0026].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have taken the method of Xu and added a thermal degreasing step with a temperature of 500 – 800°C and a holding time of 0 – 180 min following catalytic degreasing, as disclosed by CN ‘576. Xu, Bose, and CN ‘576 are directed to metal injection molding of similar alloy compositions and as such, an ordinarily skilled artisan would have considered the teachings of Bose and CN ‘576 to be reasonably pertinent to the method of Xu and would have had a reasonable expectation of success in applying said teachings. Moreover, as disclosed by Bose using two step debinding allows for slower and more complete removal of a multicomponent binder (wherein Xu teaches a multicomponent binder [0071, 0155]) such that the green part successfully retains its shape. CN ‘576 also teaches that thermal degreasing below the sintering temperature prevents the binder from breaking down into carbon and oxygen. As such, an ordinarily skilled artisan would have been motivated to have applied an additional thermal degreasing step in the temperature and time disclosed by CN ‘576.
Moreover, it would have been obvious to one of ordinary skill in the art before the effective filing date to have used the inert gas pressure range of 0 – 100 kPa, which overlaps with the claimed range, as the sintering pressure in the sintering step of Xu to achieve predictable results. Both Xu and CN ‘576 are directed to sintering steel alloys in an inert gas atmosphere after injection molding and as such, an ordinarily skilled artisan would have had a reasonable expectation of success in applying the teachings with no change in their respective functions. The combination of prior art elements to yield predictable results is a prima facie case of obviousness (See MPEP 2143 A). Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I).
Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Response to Arguments
Applicant's amendments have overcome the previous rejections. However, upon further consideration a new rejection is made of:
Claims 5 – 8 and 11 under 35 U.S.C. 103 as being unpatentable over Xu (US2023/0212721) in view of Bose (ASM Handbook, “Metal Powder Injection Molding”, NPL, 2015), Sato (JP2014/208869) and Diekman (ASM Handbook, “Cold and Cryogenic Treatment of Steel”, 2013)
Claim 6 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 5, in further view of Nakamura (US2018/0009031)
Claim 9 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 5, in further view of Ge (CN113969378)
Claim 10 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 5, in further view of Xu (CN113560576, referred to as CN ‘576 for clarity)
Claims 12 – 13 and 15 – 19 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, Xu (CN113560576, referred to as CN ‘576 for clarity), and Heuer (ASM Handbook, “Gas Quenching”, 2013).
Claim 14 under 35 U.S.C. 103 as being unpatentable over X Xu in view of Bose, Sato, and Diekman, Xu (CN113560576, referred to as CN ‘576 for clarity), and Heuer, as applied to claim 12, in further view of Thomas (NPL, “Pit Furnace”, 2019)
Claim 20 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman.
Claim 21 rejected under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 20, in further view of Xu (CN113560576, referred to as CN ‘576) and Heuer.
Claim 22 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 20, in further view of Xu (CN113560576, referred to as CN ‘576 for clarity).
Claim 23 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 20, in further view of Ge.
Claim 24 under 35 U.S.C. 103 as being unpatentable over Xu in view of Bose, Sato, and Diekman, as applied to claim 20, in further view of Xu (CN113560576, referred to as CN ‘576 for clarity)
The arguments filed 03/13/2026 have been fully considered but they are not persuasive.
Applicant argues that the prior art does not teach forming a sintered product having a yield strength of less than 800 MPa and then forming a component with a yield strength of at least 1800 MPa. Applicant argues that all the examples of Xu have a yield strength lower than 1800 MPa. This is not found persuasive. Xu teaches that the yield strength of the formed component is 2000 MPa or less [0015], which overlaps with the claimed range. A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989)(MPEP 2123 I) Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971) (MPEP 2123 II)
Applicant argues that the prior art does not teach forming a sintered product having a hardness or yield strength as claimed and then forming a component with a hardness of 500 – 650 HV or yield strength of 1800 MPa or less. While Xu does not expressly teach the hardness or yield strength of the sintered component prior to heat treatment, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu teaches a substantially identical method of mixing, injection molding, degreasing, and sintering. As such, there is a reasonable expectation to an ordinarily skilled artisan that the sintered component of Xu would possess the claimed hardness and yield strength. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Likewise, in regards to the hardness of the final component. Xu does not expressly teach the hardness of the final component after heat treatment. However, Xu teaches a substantially overlapping composition to the claimed composition, a final yield strength that overlaps with the claimed range, and an elongation [0016] that overlaps with the instant invention [0075 of pg-pub]. Moreover, Xu as-modified teaches a substantially identical method of mixing, injection molding, degreasing, and sintering as well as solutionizing, treating at sub-zero temperatures, and aging. As such, there is a reasonable expectation to an ordinarily skilled artisan that the component of Xu as-modified would possess the claimed hardness. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, in this case composition, structure (i.e., properties), and method, a prima facie case of obviousness is established (In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (SEE MPEP 2112.01))
Applicant argues that the prior art does not teach solutionizing in a vacuum. This is not found persuasive. CN ‘576 teaches that the solutionizing and aging treatment can be conducted under vacuum [0037, 0038]. A person possessing ordinary skill in the art would reasonably understand that vacuum atmospheres are known for being protective from impurities/oxidation during heat treatment and as such, would be motivated to apply vacuum to prevent this. This is evidenced by Xu, which explicitly notes vacuum as a protective atmosphere [0171].
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/AUSTIN POLLOCK/Examiner, Art Unit 1738
/BRIAN D WALCK/Primary Examiner, Art Unit 1738
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