DETAILED ACTION
Notice of Pre-AIA or 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 .
Applicant amended Claim 1. Claim 3 is canceled. Applicant added Claims 16-19. Support for the amendments and new claims is found in the original filing. No new matter is presented.
Information Disclosure Statements
The information disclosure statements (IDS) submitted on 03/24/2025 has been considered by the examiner.
Continued Examination Under 37 CFR 1.114
Receipt is acknowledged of a request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) and a submission, filed on 02/02/2026.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-2, 4-9, and 12-16 are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as anticipated by NPL Singhal et al.
Regarding Claims 1 and 2, NPL Singhal et al. discloses a method for manufacturing a recycled aluminum metal compact (meeting the limitation for a recycled aluminum metal lump) formed from aluminum powder scrap, the method comprising compressing the aluminum metal followed by irradiating aluminum metal with a microwave (Pages 559-560, Figure 2). The limitation regarding the absence of dendrites is not required to meet the limitations of instant Claim 1. Further, it is noted NPL Singhal et al. teaches metallographic images showing no dendrite formation in the manufactured product (Figure 6).
NPL Singhal et al. discloses an exemplary sintered density of 2.538 grams per centimeters cubed in the manufactured product (Abstract), meeting the limitations of the instant Claim.
Regarding Claims 4 and 7, NPL Singhal et al. discloses performing compressing the aluminum metal before irradiating with the microwave (Figure 2), meeting the limitations for the instant Claims.
Regarding Claims 5-6 and 8-9 , NPL Singhal et al. discloses the compressing of the aluminum metal is performed using a crucible (Page 561)(meeting the limitation for a molding box), meeting the limitations for the instant Claims.
Regarding Claim 12-15, NPL Singhal et al. discloses compressing the aluminum metal in a crucible (Page 561)(meeting the limitation for a molding box), ultimately forming a shaped recycled aluminum metal lump product (Figure 3), meeting the limitations for the instant Claims.
Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01(a) I.
Regarding Claim 16, NPL Singhal et al. discloses subjecting fortifying the aluminum metal powder with silicon carbide particles (Page 563), meeting the limitations of the instant Claim.
Claim Rejections - 35 USC § 103
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.
The factual inquiries 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.
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.
Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Singhal et al. as applied to Claims 1-2, 4-9, and 12-16 above, further in view of NPL Xu et al.
Regarding Claims 10-11, NPL Singhal et al. teaches the limitations set forth above and further teaches improvements in mechanical properties of metal castings and decreased grain coarsening are achieved due to short processing time at (Page 560). NPL Singhal et al. teaches metallographic images showing no dendrite formation (Figure 6).
NPL Singhal et al. however does not expressly disclose the aluminum metal lump does not contain dendrites in its internal structure after applying pressure during irradiating the aluminum metal with the microwave.
The transposition of method steps is prima facie obvious absent a showing of new or unexpected results. See MPEP 2144.04 IV. C. Nonetheless, NPL Xu et al., teaches external pressure applied to aluminum oxide powder during sintering enhances the densification process (Introduction, Page 636) and reduces grain coarsening (Introduction, Page 635).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to perform the compression step of NPL Singhal et al. during irradiation with the microwave in order to prevent the formation of air gaps in the finished aluminum product and enhance the densification process and reduce grain coarsening based on the teachings of NPL Xu et al. e.g. at (Introduction, Pages 635-636), meeting the limitations of the instant Claims.
Claims 17 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Singhal et al. as applied to Claims 1-2, 4-9, and 12-16 above, further in view of NPL Chhillar et al.
Regarding Claim 17, NPL Singhal et al. discloses the limitations set forth above but does not expressly teach the method is carried out in a reducing atmosphere.
However, NPL Chhillar et al. teaches the microwave sintering of compressed molybdenum metal powder in a reducing atmosphere in order to reduce oxidation (Page 183). Though NPL Chhillar et al. teaches a different metal composition, the microwave sintering of metal powder is analogous art.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to conduct the method of NPL Singhal et al. in a reducing environment in order to reduce the effects of oxidation and presence of foreign impurity in the produced product based on the teachings of NPL Chhillar et al. at (Page 183) and the teachings of NPL Singhal et al. at (Abstract, Page 563).
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Singhal et al. as applied to Claims 1-2, 4-9, and 12-16 above, further in view of NPL Venkateswarlu et al.
Regarding Claim 18, NPL Singhal et al. teaches the limitations set forth above. NPL Singhal teaches a sintering time of 15 minutes (900 seconds), a processing time which overlaps the instantly claimed range of 60 seconds to 300 seconds. However, insofar as manufacturing the recycled metal lump in the instantly claimed time range, NPL Singhal et al. does not expressly teach the irradiating with the microwave is carried out for a time of 60 seconds to 300 seconds.
However, NPL Venkateswarlu et al. teaches microwave sintering of an aluminum metal matrix composite for two minutes (120 seconds) in order to achieve optimized hardness and densification of the compacted metal (Page 231); the time of 120 seconds lies within the instantly claimed range of 60 seconds to 300 seconds.
See MPEP 2144.05. In cases where 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to sinter the aluminum metal chip of NPL Rangel et al. for 120 seconds in order to achieve increased hardness and densification of the resultant metal compact based on the teachings of Venkateswarlu et al. at (Page 232). One of ordinary skill in the art at the time of filing the invention would be motivated by a desire to optimize hardness and density to vary sintering times, meeting the limitations of the instant Claim.
"[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).
Claim 19 is rejected under 35 U.S.C. 103 as being unpatentable over of NPL Singhal et al. as applied to Claims 1-2, 4-9, and 12-16 above, further in view of NPL Ao et al.
Regarding Claim 17, NPL Singhal teaches the limitations set forth above but does not expressly teach the recycled aluminum metal lump has an internal structure composed of a granular Si phase and an aluminum eutectic.
However, NPL Ao et al. teaches the morphology of aluminum alloyed with silicon, with an internal structure composed of a granular Si phase and an aluminum eutectic is achieved by varying heat treatment temperature and silicon composition (Page 110049).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to vary the heat treatment temperature and silicon concentration below the eutectic temperature of aluminum and below the eutectic composition of silicon in order to reduce the agglomeration of silicon and increase mechanical strength of the metal product based on the teachings of NPL Singhal et al. at (Page 565). One of ordinary skill in the art at the time of filing the invention would expect such temperatures and processing below the eutectic temperature to present the same or similar morphology of eutectic aluminum and granular silicon based on the teachings of NPL Ao et al. e.g. at (Page 110049), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[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).
Claims 1-2, 4-9, and 12-15 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al.
Regarding Claims 1-2, 4, and 7, NPL Rangel et al. teaches a method for manufacturing a recycled aluminum metal block (meeting the limitation for a recycled aluminum metal lump) formed from aluminum chip (Section 2), the method comprising irradiating aluminum metal including aluminum scrap with a microwave and compressing the aluminum metal (Sections 1-3, Figs. 1-3).
NPL Rangel et al. does not expressly disclose the density of the recycled aluminum metal lump.
However, the density of aluminum is known to be 2.70 g/cm3 as evidenced by NPL Abd El Aal et al. at (Section 3.1). Additionally, NPL Abd El Aal et al. evidences the relative density of aluminum chip (aluminum which has undergone heat and compaction) may vary from 93% to 99.6% the density of aluminum (2.51 g/cm3 to 2.69 g/cm3) (Section 3.1), meeting the limitation of the instant Claim for a density from 2.00 g/cm3 to 2.70 g/cm3.
NPL Rangel et al. teaches performing compressing the aluminum metal after radiating with the microwave (Section 2), but does not expressly teach compressing the aluminum metal prior to, or during irradiation with a microwave.
However, the transposition of method steps is prima facie obvious absent a showing of new or unexpected results. See MPEP 2144.04 IV. C.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to perform the compression step of NPL Rangel et al. prior to, or during irradiation with the microwave in order to prevent the formation of air gaps in the finished aluminum product. Applicant is encouraged to present a showing of new or unexpected results. The limitation regarding the absence of dendrites is not required to meet the limitations of instant Claim 1. Further, it is noted NPL Rangel teaches metallographic images showing no dendrite formation in the manufactured product (Figure 5).
Regarding Claim 5-6, 8-9, and 12-15, NPL Rangel et al. teaches compressing the aluminum metal in a crucible (Section 2)(meeting the limitation for a molding box), ultimately forming a shaped recycled aluminum metal lump product (Figure 3), meeting the limitations for the instant Claims.
Generally, changes in shape will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such shape is critical. See MPEP 2141.01(a) I.
Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al. as applied to Claims 1-2, 4-9, and 12-15 above, further in view of NPL Xu et al.
Regarding Claims 10-11, NPL Rangel et al. teaches the limitations set forth above and further teaches improvements in mechanical properties of the aluminum casting are achieved due to short processing time at (Section 1). NPL Rangel teaches metallographic images showing no dendrite formation (Figure 5).
NPL Rangel et al. however does not expressly teach the aluminum metal lump does not contain dendrites in its internal structure after applying pressure during irradiating the aluminum metal with the microwave.
As set forth above, the transposition of method steps is prima facie obvious absent a showing of new or unexpected results. See MPEP 2144.04 IV. C.
Nonetheless, NPL Xu et al., teaches external pressure applied to aluminum oxide powder during sintering enhances the densification process (Introduction, Page 636) and reduces grain coarsening (Introduction, Page 635).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to perform the compression step of NPL Rangel et al. during irradiation with the microwave in order to prevent the formation of air gaps in the finished aluminum product and enhance the densification process and reduce grain coarsening based on the teachings of NPL Xu et al. e.g. at (Introduction, Pages 635-636), meeting the limitations of the instant Claims.
Claims 16 are rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al. as applied to Claims 1-2, 4-9, and 12-15 above, further in view of NPL Singhal et al.
Regarding Claim 16, NPL Rangel et al. teaches the limitations set forth above but does not expressly teach the aluminum metal lump comprises silicon (Si).
However, NPL Singhal et al. teaches reinforcing aluminum metal powder with silicon carbide particles in order to increase the density of the sintered product, compressing to form a compact, and subjecting the compact to microwave sintering e.g. at (Page 563).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to fortify the aluminum chip in the aluminum metal block (meeting the limitation for a recycled aluminum metal lump) of NPL Rangel et al. with silicon carbide particles in order to increase the density of the sintered product, based on the teachings of NPL Singhal et al. at (Page 563), meeting the limitations of the instant Claim.
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al. as applied to Claims 1-2, 4-9, and 12-15 above, further in view of NPL Chhillar et al.
Regarding Claim 17, NPL Rangel et al. teaches the limitations set forth above but does not expressly teach the method is carried out in a reducing atmosphere.
However, NPL Chhillar et al. teaches the microwave sintering of compressed molybdenum metal powder in a reducing atmosphere in order to reduce oxidation (Page 183). Though NPL Chhillar et al. teaches a different metal composition, the microwave sintering of metal powder is analogous art.
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to conduct the method of NPL Rangel et al. in a reducing environment in order to reduce the effects of oxidation in the produced product based on the teachings of NPL Chhillar et al. at (Page 183).
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al. as applied to Claims 1-2, 4-9, and 12-15 above, further in view of NPL Venkateswarlu et al.
Regarding Claim 18, NPL Rangel et al. teaches the limitations set forth above but does not expressly teach the irradiating with the microwave is carried out for a time of 60 seconds to 300 seconds.
However, NPL Venkateswarlu et al. teaches microwave sintering of an aluminum metal matrix composite for two minutes (120 seconds) in order to achieve optimized hardness and densification of the compacted metal (Page 231); the time of 120 seconds lies within the instantly claimed range of 60 seconds to 300 seconds.
See MPEP 2144.05. In cases where 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to sinter the aluminum metal chip of NPL Rangel et al. for 120 seconds in order to achieve increased hardness and densification of the resultant metal compact based on the teachings of Venkateswarlu et al. at (Page 232). One of ordinary skill in the art at the time of filing the invention would be motivated by a desire to optimize hardness and density to vary sintering times, meeting the limitations of the instant Claim.
"[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).
Claim 19 is rejected under 35 U.S.C. 103 as being unpatentable over NPL Rangel et al. as evidenced by NPL Ab El Aal et al. further in view of NPL Singhal et al. as applied to Claim 16 above, further in view of NPL Ao et al.
Regarding Claim 19, NPL Rangel et al. modified by NPL Singhal et al. teaches the limitations set forth above but does not expressly teach the recycled aluminum metal lump has an internal structure composed of a granular Si phase and an aluminum eutectic.
However, NPL Ao et al. teaches the morphology of aluminum alloyed with silicon, with an internal structure composed of a granular Si phase and an aluminum eutectic can be achieved by varying heat treatment temperature and silicon composition (Page 110049).
It would have been obvious to one having ordinary skill in the art at the time of filing the invention to vary the heat treatment temperature and silicon concentration below the eutectic temperature of aluminum and below the eutectic composition of silicon in order to reduce the agglomeration of silicon and increase mechanical strength of the metal product based on the teachings of NPL Singhal et al. at (Page 565). One of ordinary skill in the art at the time of filing the invention would expect such temperatures and processing below the eutectic temperature to present the same or similar morphology of eutectic aluminum and granular silicon based on the teachings of NPL Ao et al. e.g. at (Page 110049), meeting the limitations of the instant Claim.
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[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).
Response to Arguments
Applicant's arguments filed 02/02/2026 have been fully considered but they are not deemed persuasive as to the prior art rejections.
Applicant argues the cited references do not teach or suggest microwaving aluminum scrap after or during compression. However, as set forth above, the transposition of method steps is prima facie obvious absent a showing of new or unexpected results. See MPEP 2144.04 IV. C. It would have been obvious to one having ordinary skill in the art at the time of filing the invention to perform the compression step of NPL Rangel et al. prior to, or during irradiation with the microwave in order to prevent the formation of air gaps in the finished aluminum product.
Applicant further argues previously cited prior art is silent as to the presence of dendrites. However, Applicant discloses in the instant Specification, e.g. at [0054], the presence of dendrites is a result of a short processing time. As set forth above, NPL Rangel et al. and NPL Singhal et al. both teach improvements in mechanical properties of metal castings and decreased grain coarsening are achieved due to short processing time at (Section 1) and (Page 560) respectively.
Applicant is encouraged to present a showing of new or unexpected results. Additionally, “[A] reference need not be from the same field of endeavor as the claimed invention in order to be analogous art.” Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212. The method of producing recycled aluminum in NPL Rangel et al. overlaps and encompasses the instantly claimed method steps. Without more, the rearrangement of steps would have been obvious to a person of ordinary skill in the art at the time of filing the invention. As set forth above, NPL Singhal et al. discloses a method of forming an aluminum compact meeting the limitations of the instant Claims.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
CN 111548142 A teaches dry pressing metal-oxide powders into a ceramic sheet prior to microwave sintering.
Agrawal, Dinesh. “Microwave Sintering, Brazing and Melting of Metallic Materials.” Sohn International Symposium; Advanced Processing of Metals and Materials Volume 4: New, Improved and Existing Technologies: Non-Ferrous Materials Extraction and Processing 4 (2006): 183–192. teaches applying microwaves to melt, heat treat, and sinter metal powders.
WO 2018015492 A1 teaches compressing aluminum scrap into billets or blocks having a density of 1.8-2.4 g/cm3.
Yoshikawa, N. "Microwave processing of metallic materials." IOP Conference Series: Materials Science and Engineering. Vol. 424. No. 1. IOP Publishing, 2018. teaches microwaving metallic materials.
CN 101624663 A teaches microwave sintering a high-density metal alloy for 2-5 minutes.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/M.S.S./Examiner, Art Unit 1733