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 .
Election/Restrictions
Applicant's election with traverse of Group I, claims 1-8, in the reply filed on 16 April 2026, is acknowledged. The traversal is on the ground(s) that it would not be a serious burden to search and examine the entire application. This is not found persuasive because applicant is reminded that the instant application is a national stage entry under 35 USC 371 and the burden of restriction is Unity of Invention. The examiner has properly shown in the Office Action mailed 19 February 2026 that Evans in view of Clark teaches applicant’s technical feature common to groups I and II. As such, said special technical feature is considered to be neither novel nor inventive a posteriori over the prior art and therefore the instant groups lack Unity of Invention. See MPEP § 1893.03(d).
The requirement is still deemed proper and is therefore made FINAL.
Claims 9-13 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 16 April 2026.
Drawings
The drawings are objected to as failing to comply with 37 CFR 1.84(p)(4) because the following parts are referenced by more than one reference character:
Reference characters "A" and "1" have been used to designate a steel part (p. 8-9 for Figs. 1, 5, and 6)
Reference characters “C”, “2”, and “A” have been used to designate a cemented carbide part (p. 8-9 for Figs. 1 and 5-9)
The drawings are objected to as failing to comply with 37 CFR 1.84(p)(4) because the following reference characters have been used to designate more than one part:
Reference character “A” has been used to designate a steel part (p. 8 for Figs. 1 and 5), a cemented carbide part (p. 9 for Figs. 7-9), a step of providing a cemented carbide part (p. 9 for Fig. 10), and a cemented carbide supported PCD part (p. 9 for Fig. 11).
Reference character “B” has been used to designate a braze joint (p. 8 for Figs. 1 and 5), a maraging steel part (p. 9 for Figs. 7-9 and 11), and a step of providing a maraging steel part (p. 9 for Fig. 10)
Reference character “C” has been used to designate a cemented carbide support (p. 8 for Fig. 1), a cemented carbide (p. 8 for Fig. 5), and a step of placing a braze material (p. 9 for Fig. 10).
Reference character “D” has been used to designate a superhard compact (p. 8 for Fig. 1) and a brazing step (p. 9 for Fig. 10)
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
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.
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 (i.e., changing from AIA to pre-AIA ) 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.
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 1-4 and 7-8 are rejected under 35 U.S.C. 103 as being unpatentable over Evans et al. (US 2018/0010397, previously cited) in view of Clark et al. (US 2018/0169796, previously cited).
Claim 1: Evans teaches a cutting element (i.e. a cutting tool) that includes a superhard material and a low-carbon steel material (paragraph 0001). The cutting element may include a table of superhard material such as a polycrystalline diamond material compact material (a PCD material) that directly overlies and contacts a substrate (i.e. bonded to a substrate) (paragraph 0024), wherein the substrate may include a cemented carbide material (paragraph 0025). The substrate may directly overlie and contact a low-carbon steel material (paragraph 0026), such as a maraging steel (paragraph 0029), having a hardness of about 43-60 Rockwell C (i.e. about 423-697 HV) after aging and hardening (paragraph 0062). This hardness range overlaps the instantly claimed hardness, and the courts have held that a prima facie case of obviousness exists where claimed ranges overlap, lie inside of, or are close to ranges in the prior art. See MPEP § 2144.05. It is noted that as of the writing of this Office Action, no demonstration of a criticality to the claimed ranges has been presented. Evans does not specify the standard deviation of the hardness values; however, this property is considered to be present due to being a maraging steel. It is noted that the instant specification demonstrates a standard higher than the claimed range only for steel 1.6582 which was not a maraging steel (i.e. Comparative Example 2 in the instant specification). Evans teaches that prior art may include a braze material between the steel material and substrate which may expose the PCD table to undesirably elevated temperatures (paragraph 0064). Since the steel is annealed at a temperature less than about 900°C, such as between about 800-900°C (paragraph 0054), temperatures higher than 900°C presumably would be considered undesirable. However, Evans does not teach the material of braze material.
In a related field of endeavor, Clark teaches joining articles by brazing (paragraph 0001), such as for cutters (i.e. cutting tools) (paragraphs 0096-0102 and 0110). Clark further teaches that a braze joint can help reduce problems from CTE mismatch (paragraph 0014), being a region of lower stiffness than the materials being joined (paragraph 0023). The resulting vibration stress can be reduced by providing a braze in which part at least comprises a material capable of age hardening at a temperature below the brazing temperature and above the application temperature and by joining the articles together at a brazing temperature followed by heat treating the brazed assembly to age harden the filler at least in part (paragraphs 0023-0026). Active brazes include brazes that comprise one or more carbide-forming elements in sufficient amount to form covalent bonds where in contact with the adjoining (presumably carbon-containing) surface, wherein suitable elements include titanium and chromium (paragraph 0029). Although primarily directed to brazing diamonds to tungsten carbide, Clark teaches that the joined article may include brazed joints between different materials such as diamond brazed to carbide brazed to metal (paragraph 0089) (i.e. the brazed joint may be used between a carbide and a metal). It is noted that each of the brazing and heat treatments disclosed by Clark are at temperatures of 845°C or lower (paragraphs 0038-0053 and 0060-0069), which permits age hardening to occur during cooling rather than as an additional post braze process (paragraph 0077).
Clark teaches the titanium as a carbide forming element (paragraph 0029) but does not specifically teach a thickness of the TiC layer adjoining the cemented carbide substrate. However, Clark teaches brazing a cemented tungsten carbide part using an Ag-Cu-Ti active brazing alloy (“Cusil-ABA® alloy”) containing 1.75% Ti, as a foil with a thickness of 0.05 mm (i.e. about 50 µm) in a vacuum furnace (paragraphs 0034, 0095) at a temperature between 685-815°C for a time period of about 20-30 minutes (paragraphs 0034-0042). This compares to the instantly disclosed brazing conditions of temperature between 600-780°C, for a time period of 1-60 minutes in a vacuum and using a braze material containing Ti in an amount of 0.3-15 wt% of the braze material, preferably 1-5%, and including one or more elements of Ag, Cu, etc. (p. 6-7 of the instant specification), as a foil or paste with a thickness of 20-200 µm (p. 7 of the instant specification). Furthermore, Clark teaches an ageing step (heat treatment) at a temperature of between 425-540°C for about 3-6 hours (paragraphs 0050-0052) to age harden the brazing filler at least in part (paragraphs 0026-0027), which compares to the instantly disclosed ageing step at a temperature of 300-600°C for between 5 minutes and 12 hours (p. 6 of the instant specification). Each of the ranges taught by Clark overlap the ranges of the instant disclosure. See MPEP § 2144.05. Furthermore, since Clark teaches a substantially identical braze material and process, the resulting TiC layer thickness is considered to be present because substantially identical materials treated in substantially identical manner have substantially identical properties and functions, absent an objective showing. See MPEP § 2112.01.
As Evans and Clark both teach a cutting tool, they are analogous. Furthermore, Evans teaches that prior art may include a braze material between the steel material and substrate which may expose the PCD table to undesirably elevated temperatures (paragraph 0064) (i.e. temperatures higher than 900°C would be considered undesirable) whereas Clark teaches a braze in which part at least comprises a material capable of age hardening at a temperature below the brazing temperature and above the application temperature and by joining the articles together at a brazing temperature followed by heat treating the brazed assembly to age harden the filler at least in part (paragraphs 0023-0026), and it is noted that each of the brazing and heat treatments disclosed by Clark are at temperatures of 845°C or lower (paragraphs 0038-0053 and 0060-0069), which permits age hardening to occur during cooling rather than as an additional pose braze process (paragraph 0077). It would have been obvious to one of ordinary skill in the art before the effective filing date to modify the cutting tool of Evan to include a braze between the steel material and the substrate (i.e. the cemented carbide substrate) using the braze and brazing technique of Clark because Clark teaches the braze joint can help reduce problems from CTE mismatch (paragraph 0014), and one would have had a reasonable expectation of success.
Claim 2: Evans teaches that the substrate may directly overlie and contact a low-carbon steel material (paragraph 0026), such as a maraging steel (paragraph 0029), having a hardness of about 43-60 Rockwell C (i.e. about 423-697 HV) after aging and hardening (paragraph 0062). This hardness range overlaps the instantly claimed hardness. See MPEP § 2144.05. Evans does not specify the standard deviation of the hardness values; however, this property is considered to be present due to being a maraging steel. It is noted that the instant specification demonstrates a standard higher than the claimed range only for steel 1.6582 which was not a maraging steel (i.e. Comparative Example 2 in the instant specification).
Claim 3: Clark teaches brazing a cemented tungsten carbide part using an Ag-Cu-Ti active brazing alloy (“Cusil-ABA® alloy”) containing 1.75% Ti, as a foil with a thickness of 0.05 mm (i.e. about 50 µm) in a vacuum furnace (paragraphs 0035, 0095) (i.e. a braze joint with a thickness of about 50 µm), which overlaps the instantly claimed range. See MPEP § 2144.05.
Claim 4: Clark teaches the shear strength of the resultant brazed joints of specific examples as being about 404-430 MPa (Table 1), which overlaps the instantly claimed range. See MPEP § 2144.05.
Claims 7-8: Evans teaches that the low-carbon steel (i.e. the maraging steel) may include iron (i.e. a balance Fe), less than 0.02 wt% carbon, and between about 15.0 weight percent and 20.0% nickel, about 5.0-20.0% cobalt, 2.0-6.0% molybdenum, 0.1-2.0% titanium, 0.05-0.15% aluminum, etc. (paragraphs 0029-0030). These elements and amounts overlap the instantly claimed content of the maraging steel (i.e. about 0% Cr, and about 0% Mn, P, and S). See MPEP § 2144.05.
Claims 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over Evans et al. (US 2018/0010397, previously cited) in view of Clark et al. (US 2018/0169796, previously cited) as applied to claim 1 above, and further in view of Chen et al. (US 2017/0304959).
Claim 5: The teachings of Evans in view of Clark regarding claim 1 are outlined above. Evans teaches a cutting element having a superhard material on a substrate of cemented carbide that is on a low-carbon steel such as maraging steel (paragraphs 0024-0026 and 0029). Evans further teaches that a braze material may be included between the steel material and substrate (paragraph 0064). Clark teaches active brazes include brazes that comprise one or more carbide-forming elements in sufficient amount to form covalent bonds where in contact with the adjoining (presumably carbon-containing) surface, wherein suitable elements include titanium and chromium (paragraph 0029), and can be used to form a joined article with brazed joints between different materials such as carbide brazed to metal etc. (paragraph 0089). Clark teaches brazing a cemented tungsten carbide part using an Ag-Cu-Ti active brazing alloy (“Cusil-ABA® alloy” containing 63% Ag) containing 1.75% Ti, as a foil with a thickness of 0.05 mm (i.e. about 50 µm) in a vacuum furnace (paragraphs 0034, 0095). However, these references do not teach where the braze joint further includes In.
In a related field of endeavor, Chen teaches a braze material for an earth-boring tool (i.e. a cutting tool) having silver, copper, at least one element selected from nickel and titanium (i.e. containing Ti would be an obvious choice), and at least one element selected from indium, etc. (paragraph 0012) (i.e. the braze joint includes Cu, Ag, In and Ti). Chen teaches that the braze material may include a first composition and a second composition selected to form a mixture upon brazing and one may have a relatively lower solidus or melting point than the other (paragraph 0031) as a mixture of low- and high-melting-point materials processed at relatively low temperatures may form a relatively high-melting-point joint (paragraph 0037). Chen further specifies that indium may be selected as a low-melting-point composition of a braze for bonding a cobalt-containing body such as a cobalt-cemented tungsten carbide to an iron-containing body such as steel (paragraph 0058). In the case of a mixture of Ag and In, which may have additional elements in the braze material, In exhibits a melting point of about 157°C and Ag exhibits a melting point of about 962°C such that In will melt before the Ag melts and the melted In may diffuse into and around the particles of solid Ag and may form one or more phases having higher melting points (paragraph 0042).
As Clark and Chen both teach a brazing material for brazing a cemented carbide to steel, they are analogous. It would have been obvious to one of ordinary skill in the art before the effective filing date to modify the cutting element of Clark-modified Evans to include where the braze material includes In as a low-melting-point composition so that the brazing can be processed at relatively low temperatures and form a relatively high-melting-point joint as taught by Chen, and one would have had a reasonable expectation of success.
Claim 6: Clark teaches using an Ag-Cu-Ti active brazing alloy (“Cusil-ABA® alloy” containing 63% Ag, 35.25% Cu, and 1.75% Ti) (paragraph 0034). Chen does not teach a specific general range for the content of In, but specific examples contained about 2 or 4 wt% In in the braze composition (Tables 3 and 4, respectively). Alternatively, similar to Example 2 but using 25% In instead of Zn for the low-melting-point constituent and 75% Cusil-ABA® alloy for the alloy precursor (i.e. based on the teachings of Clark, modified by adding In as a low-melting-point constituent as taught by Chen) would result in a braze composition containing about 47.3% Ag, 26.4% Cu, 1.3% Ti, and 25% In, and these ranges overlap the instantly claimed ranges. See MPEP § 2144.05.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1-4 and 7-8 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-3 and 6-7 of U.S. Patent No. 12,350,752 in view of Evans et al. (US 2018/0010397, previously cited).
Instant claim 1 and claim 1 of the ‘752 patent both recite a tool comprising a cemented carbide, a maraging steel part, and a braze joint joining the cemented carbide and the maraging steel part.
Instant claim 1 recites the maraging steel part as having a hardness of between 350 and 580 HV1 with a standard deviation between 0 and 20 HV1, whereas claim 1 of the ‘752 patent recites the maraging steel part as having a hardness of between 350 and 600 HV1 with a standard deviation between 0 and 20 HV1. These ranges overlap and the courts have held that a prima facie case of obviousness exists where claimed ranges overlap, lie inside of, or are close to other ranges. See MPEP § 2144.05. It is noted that as of the writing of this Office Action, no demonstration of a criticality to the claimed ranges has been presented.
Instant claim 1 and claim 1 of the ‘752 patent both recite the braze joint includes Ti and wherein said braze joint includes a TiC layer with a thickness of between 0.03 and 5 µm adjoining the cemented carbide part.
Instant claim 1 differs from the ‘752 patent insofar as reciting the tool as being a cutting tool; however, this difference is considered to be a matter of intended use and associated (obvious) change of shape, that does not provide a patentable distinction absent an objective showing of significance.
Instant claim 1 also differs from the ‘752 patent insofar as reciting a superhard part bonded to the cemented carbide (substrate).
In a related field of endeavor, Evans teaches a downhole tool including cutting elements (paragraph 0009) having a hardened low-carbon steel material such as a maraging steel material that further includes one or more cutting elements (paragraph 0023). Cutting elements may include a table of superhard material such as polycrystalline diamond material overlying a substrate (paragraph 0024) wherein the substrate may include a cemented carbide material (paragraph 0025). Evans teaches that prior art cutting elements may include a braze material between the steel material and substrate (i.e. the cemented carbide substrate).
As Evans teaches a tool having a braze joint joining a cemented carbide part and a maraging steel part, it is analogous. It would have been obvious to one of ordinary skill in the art before the effective filing date to modify the ‘752 patent to include a superhard part bonded to the cemented carbide substrate as this is considered a conventionally known feature of a (cutting) tool, and one would have had a reasonable expectation of success.
Instant claim 2 recites wherein the maraging steel part has a hardness of between 400 and 580 HV1 with a standard deviation of between 0 and 14 HV1, whereas claim 1 of the ‘752 patent recites wherein the maraging steel part has a hardness of between 400 and 460 HV1 with a standard deviation of between 0 and 14 HV1. These ranges overlap. See MPEP § 2144.05.
Instant claim 3 recites wherein the braze joint has a thickness of between 5 and 200 µm, whereas claim 2 of the ‘752 patent recites wherein the braze joint has a thickness of between 20 and 200 µm. These ranges overlap. See MPEP § 2144.05.
Instant claim 4 and claim 3 of the ‘752 patent both recite wherein a shear strength of the braze joint is at least 130 MPa.
Instant claim 7 recites substantially identical limitations as claim 6 of the ‘752 patent.
Instant claim 8 recites wherein the maraging steel includes from 17 to 19 wt% Ni, from 8.5 to 12.5 wt% Co, from 4 to 6 wt% Mo, from 0.5 to 1.2 wt% Ti, from 0 to 0.15 wt% Cr, from 0 to 0.2 wt% Al, less than 0.3 wt% C, and balance Fe, whereas claim 7 of the ‘752 patent recites wherein the maraging steel includes 13 to 25 wt% Ni, 7 to 15 wt% Co, 3 to 10 wt% Mo, 0.1 to 1.6 wt% Ti, 0.05 to 0.15 wt% Cr, 0 to0.2 wt% Al, less than 0.3 wt% C and balance Fe. It is noted that instant claim 8 also recites less than 0.1 wt% of any of Mn, P, and S, whereas claim 7 of the ‘752 patent omits this limitation; however, this range also includes 0% and therefore claim 7 of the ‘752 patent is considered to overlap this range.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KIM S HORGER whose telephone number is (571)270-5904. The examiner can normally be reached M-F 9:30 AM - 4:00 PM EST.
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/KIM S. HORGER/Examiner, Art Unit 1784
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