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 .
Response to Amendment
The amendment submitted 02/10/2026 has been entered. Claims 1-2, 4-5, 9-12, 14-15, and 19-20 remain pending. Claims 3, 6-8, 13, and 16-18 have been cancelled.
The amendments to the claims have overcome each and every rejection made under 35 USC 112 in Non-Final Rejection mailed 12/31/2025 and those rejections are hereby withdrawn.
Response to Arguments
Applicant's arguments filed 02/10/2026 have been fully considered but they are not persuasive. The amendments to the claims have changed the scope of the claims necessitating modified grounds of rejection. Please see modified grounds of rejection below.
In response to applicant's argument that the examiner has combined an excessive number of references, reliance on a large number of references in a rejection does not, without more, weigh against the obviousness of the claimed invention. See In re Gorman, 933 F.2d 982, 18 USPQ2d 1885 (Fed. Cir. 1991).
The Applicant argues there is no reason to combine the teachings of Farmer with the disclosure of Webb since Farmer teaches wherein carbon fibers have greater tensile strength than SiC fibers, are less dense than SiC fibers, and as claimed require a coating therefore the teaching that carbon fibers need a coating for oxidation resistance would not be a reason to turn away from carbon fibers.
The Examiner respectfully disagrees. While the motivation to combine is “achieving a maximum strength to weight ratio”, such a benefit is due to the particular arrangement of SiC fibers taught by Farmer which would still be applicable if one of ordinary skill desired to maximizing a strength to weight ratio of SiC fibers, and one of ordinary skill may have any number of reasons to choose SiC fibers over carbon fibers; merely as an example, US 20070128421 to Lee teaches wherein SiC fibers have “better thermal stability and higher coefficient of thermal expansion” and the “oxidation resistance of the SiC fiber … is significantly greater than the best inhibited C/C or C/SiC materials”, both of which might lead one of ordinary skill to choose SiC fibers over carbon fibers.
Claim Rejections - 35 USC § 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 (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.
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.
Claim(s) 1-2, 4-5, and 9-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 11028713 to Webb in view of US US 6213720 to Farmer in further view of US 20220178262 to Sudre in even further view of US 5856252 to Lange in even further view of US 6979490 to Steffier in even further view of non-patent literature “Crack-healing performance and oxidation behavior of SiC dispersed yttrium silicate composites” to Vu.
(a) Regarding claims 1 and 4-5:
(i) Webb discloses a ceramic composite (sealing ring seal 74, Figs 3/5) comprising: a ceramic composite material (Col 6 Lns 40-42) having a generally ring shape (Fig 5), wherein the ceramic composite material comprises a ceramic matrix (Col 6 Lns 40-42).
(ii) Webb does not disclose wherein said ceramic composite material comprises unidirectionally aligned SiC fibers within the ceramic matrix.
(iii) Farmer is also in the field of composite components (see title) and teaches a ceramic composite material comprising unidirectionally aligned SiC fibers (Col 4 Lns 16-19/41-47) within a ceramic matrix (Col 4 Lns 16-19).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic composite material as disclosed by Webb with the above aforementioned unidirectionally aligned SiC fibers as taught by Farmer for the purpose of achieving a maximum strength to weight ratio (Col 4 Lns 41-47).
(v) Webb as modified by Farmer do not teach:
wherein the unidirectional aligned fibers are coated with an interface coating;
wherein the interface coating is carbon or boron nitride; nor
wherein the interface coating includes a carbon-based layer disposed on each SiC fiber and a boron-nitride based layer disposed on the first carbon-based layer.
(vi) Sudre is also in the field of CMC components (see abstract) and teaches:
a plurality of ceramic fibers which are coated with an interface coating (see abstract);
wherein the interface coating is carbon or boron nitride (see abstract); and
wherein the interface coating includes a carbon-based layer disposed on each ceramic fiber of the plurality of ceramic fibers and a boron-nitride based layer disposed on the first carbon-based layer (see abstract).
(vii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the unidirectionally aligned SiC fibers as taught by the combined teachings of Webb as modified by Farmer with the above aforementioned interface coating as taught by Sudre for the purpose of improving durability and oxidation resistance (Par 0045) and preventing crack propagation (Par 0051).
(viii) Webb as modified by Farmer as further modified by Sudre do not teach wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers.
(ix) Lange is also in the field of CMC composites (see title) and teaches a ceramic matrix composite comprising a plurality of fibers (Col 3 Lns 10-14) wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers (Col 3 Lns 13-15).
(x) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix and fibers as taught by Webb as modified by Farmer as further modified by Sudre with the coefficients of thermal expansion as taught by Lange for the purpose of having the fibers be in residual tension and the matrix in residual compression thereby providing a damage tolerant ceramic matrix composite (Col 3 Lns 13-17).
(xi) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the grain size of the ceramic matrix is less than 2 microns.
(xii) Steffier is also in the field of ceramic composites (see title) and teaches wherein a grain size of a ceramic matrix is less than 2 microns (Col 3 Ln 65 – Col 4 Ln 5; 1 nm, or 0.001 microns, Col 6 Lns 20-23).
(xiii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix as disclosed by Webb to have a grain size as taught by Steffier for the purpose of dramatically improving near-theoretical strengths (Col 6 Lns 23-26) and increasing tensile strength by nearly an order of magnitude (Col 6 Lns 28-30).
(xiv) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the fibers are 8-15 microns in diameter.
(xv) Steffier further teaches fibers which are 15 microns in diameter (“commercially available small diameter” 15 μm ceramic fibers; Col 2 Lns 49-51).
(xvi) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the fibers as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange to be 15 microns in diameter as taught by Steffier for the purpose of providing fibers which exhibit excellent thermomechanical compatibility and creating a composite which is not initially micro-cracked (Col 2 Lns 49-56).
(xvii) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier do not teach a diffusion coating applied to the surface of the ceramic matrix composite material wherein said diffusion coating increases crack initiation resistance.
(xviii) Vu is also in the field of ceramic composites (see abstract) and teaches a diffusion coating (environmental barrier coating, see abstract) applied to a surface of a ceramic matrix composite (Introduction, first paragraph).
(xix) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix composite material as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier with the above aforementioned diffusion coating as taught by Vu for the purpose of providing a self-healing environmental barrier coating (see abstract) thereby increasing lifetime and reliability (Introduction, last sentence of paragraph 2).
(b) Regarding claim 2:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu teaches the ceramic composite sealing ring of claim 1.
(ii) Farmer further teaches wherein the ceramic matrix comprises a crystalline material comprising SiC (Col 4 Lns 18-19).
(c) Regarding claim 9:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu teaches the ceramic composite sealing ring of claim 1.
(ii) Webb as modified by Farmer as further modified by Sudre further teach wherein the unidirectionally aligned SiC fibers are completely encapsulated by the ceramic matrix (Farmer: Col 3 Lns 11-12; oxygen reaches the fibers when there are cracks in the ceramic matrix, Col 4 Lns 29-31).
(d) Regarding claim 10:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu teaches the ceramic composite sealing ring of claim 1.
(ii) Webb further wherein the sealing ring is a piston seal ring (see title) or a rotor seal ring (see abstract; rotor 64, Fig 3).
Claim(s) 11-12, 14-15, and 19-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 11028713 to Webb in view of US US 6213720 to Farmer in further view of US 20220178262 to Sudre in even further view of US 5856252 to Lange in even further view of US 6979490 to Steffier in even further view of non-patent literature “Crack-healing performance and oxidation behavior of SiC dispersed yttrium silicate composites” to Vu as evidenced by US 11149651 to Stoyanov.
(a) Regarding claim 11:
(i) Webb discloses a high-pressure compressor (52, Fig 1) of a gas turbine engine assembly (20, Fig 1) comprising:
a tie shaft (shaft 50, Figs 1-2);
a blade rotor (rotor 64, Fig 2); and
a ceramic composite piston seal ring (sealing ring seal 74, Figs 3/5) wherein the ceramic composite piston seal ring is positioned at an interface of the tie shaft and the blade rotor (Fig 3), and
wherein the ceramic composite piston seal ring comprises:
a ceramic composite material (Col 6 Lns 40-42) having a generally ring shape (Fig 5).
(ii) Webb does not disclose wherein the blade rotor is an integrated blade rotor nor wherein said ceramic nor composite material comprises unidirectionally aligned SiC fibers within a ceramic matrix.
(iii) Farmer is also in the field of composite components (see title) and teaches a ceramic composite material comprising unidirectionally aligned SiC fibers (Col 4 Lns 16-19/41-47) within a ceramic matrix (Col 4 Lns 16-19).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic composite material as disclosed by Webb with the above aforementioned unidirectionally aligned SiC fibers as taught by Farmer for the purpose of achieving a maximum strength to weight ratio (Col 4 Lns 41-47).
(v) Webb as modified by Farmer do not teach:
wherein the unidirectional aligned fibers are coated with an interface coating.
(vi) Sudre is also in the field of CMC components (see abstract) and teaches:
a plurality of ceramic fibers which are coated with an interface coating (see abstract).
(vii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the unidirectionally aligned SiC fibers as taught by the combined teachings of Webb as modified by Farmer with the above aforementioned interface coating as taught by Sudre for the purpose of improving durability and oxidation resistance (Par 0045) and preventing crack propagation (Par 0051).
(viii) Webb as modified by Farmer as further modified by Sudre do not teach wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers.
(ix) Lange is also in the field of CMC composites (see title) and teaches a ceramic matrix composite comprising a plurality of fibers (Col 3 Lns 10-14) wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers (Col 3 Lns 13-15).
(x) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix and fibers as taught by Webb as modified by Farmer as further modified by Sudre with the coefficients of thermal expansion as taught by Lange for the purpose of having the fibers be in residual tension and the matrix in residual compression thereby providing a damage tolerant ceramic matrix composite (Col 3 Lns 13-17).
(xi) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the grain size of the ceramic matrix is less than 2 microns.
(xii) Steffier is also in the field of ceramic composites (see title) and teaches wherein a grain size of a ceramic matrix is less than 2 microns (Col 3 Ln 65 – Col 4 Ln 5; 1 nm, or 0.001 microns, Col 6 Lns 20-23).
(xiii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix as disclosed by Webb to have a grain size as taught by Steffier for the purpose of dramatically improving near-theoretical strengths (Col 6 Lns 23-26) and increasing tensile strength by nearly an order of magnitude (Col 6 Lns 28-30).
(xiv) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the fibers are 8-15 microns in diameter.
(xv) Steffier further teaches fibers which are 15 microns in diameter (“commercially available small diameter” 15 μm ceramic fibers; Col 2 Lns 49-51).
(xvi) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the fibers as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange to be 15 microns in diameter as taught by Steffier for the purpose of providing fibers which exhibit excellent thermomechanical compatibility and creating a composite which is not initially micro-cracked (Col 2 Lns 49-56).
(xvii) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier do not teach a diffusion coating applied to the surface of the ceramic matrix composite material wherein said diffusion coating increases crack initiation resistance.
(xviii) Vu is also in the field of ceramic composites (see abstract) and teaches a diffusion coating (environmental barrier coating, see abstract) applied to a surface of a ceramic matrix composite (Introduction, first paragraph).
(xix) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix composite material as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier with the above aforementioned diffusion coating as taught by Vu for the purpose of providing a self-healing environmental barrier coating (see abstract) thereby increasing lifetime and reliability (Introduction, last sentence of paragraph 2).
(xx) The Examiner is taking official notice that it is well known in the art for rotors of a high pressure compressor of a gas turbine engine to be an integrated blade rotor as evidenced by Stoyanov (integrated blade rotor 62, Fig 2; Col 4 Lns 51-52).
(b) Regarding claim 12:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu as evidenced by Stoyanov teaches the high-pressure compressor of a gas turbine engine assembly of claim 11.
(ii) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu as evidenced by Stoyanov further teaches wherein the ceramic matrix comprises a crystalline material comprising SiC (Farmer: Col 4 Lns 18-19).
(c) Regarding claims 14-15:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu as evidenced by Stoyanov teaches the high-pressure compressor of a gas turbine engine assembly of claim 11.
(ii) Sudre further teaches:
wherein the interface coating is carbon or boron nitride (see abstract); and
wherein the interface coating includes a carbon-based layer disposed on each ceramic fiber of the plurality of fibers and a boron-nitride based layer disposed on the first carbon-based layer (see abstract).
(d) Regarding claim 19:
(i) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu as evidenced by Stoyanov teaches the high-pressure compressor of a gas turbine engine assembly of claim 11.
(ii) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier as even further modified by Vu as evidenced by Stoyanov further teaches wherein the unidirectional aligned tows are completely encapsulated by the ceramic matrix (Farmer: Col 3 Lns 11-12; oxygen reaches the fibers when there are cracks in the ceramic matrix, Col 4 Lns 29-31).
(e) Regarding claim 20:
(i) Webb discloses a method for making a high-pressure compressor of a gas turbine engine assembly (high pressure compressor 52 of gas turbine engine 20, Fig 1) comprising:
assembling a ceramic composite piston seal ring (sealing ring seal 74, Figs 3/5) at an interface of a tie shaft (shaft 50, Figs 1-2) and a blade rotor(rotor 64, Fig 2),
wherein the ceramic composite piston seal ring comprises a ceramic composite material (Col 6 Lns 40-42) having a generally ring shape (Fig 5).
(ii) Webb does not disclose wherein the blade rotor is an integrated blade rotor nor wherein said ceramic nor composite material comprises unidirectionally aligned SiC fibers within a ceramic matrix.
(iii) Farmer is also in the field of composite components (see title) and teaches a ceramic composite material comprising unidirectionally aligned SiC fibers (Col 4 Lns 16-19/41-47) within a ceramic matrix (Col 4 Lns 16-19).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic composite material as disclosed by Webb with the above aforementioned unidirectionally aligned SiC fibers as taught by Farmer for the purpose of achieving a maximum strength to weight ratio (Col 4 Lns 41-47).
(v) Webb as modified by Farmer as further modified by Sudre do not teach wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers.
(vi) Lange is also in the field of CMC composites (see title) and teaches a ceramic matrix composite comprising a plurality of fibers (Col 3 Lns 10-14) wherein the coefficient of the matrix thermal expansion of the ceramic matrix is below that of the fibers (Col 3 Lns 13-15).
(vii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix and fibers as taught by Webb as modified by Farmer as further modified by Sudre with the coefficients of thermal expansion as taught by Lange for the purpose of having the fibers be in residual tension and the matrix in residual compression thereby providing a damage tolerant ceramic matrix composite (Col 3 Lns 13-17).
(viii) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the grain size of the ceramic matrix is less than 2 microns.
(ix) Steffier is also in the field of ceramic composites (see title) and teaches wherein a grain size of a ceramic matrix is less than 2 microns (Col 3 Ln 65 – Col 4 Ln 5; 1 nm, or 0.001 microns, Col 6 Lns 20-23).
(x) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix as disclosed by Webb to have a grain size as taught by Steffier for the purpose of dramatically improving near-theoretical strengths (Col 6 Lns 23-26) and increasing tensile strength by nearly an order of magnitude (Col 6 Lns 28-30).
(xi) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange do not teach wherein the fibers are 8-15 microns in diameter.
(xii) Steffier further teaches fibers which are 15 microns in diameter (“commercially available small diameter” 15 μm ceramic fibers; Col 2 Lns 49-51).
(xiii) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the fibers as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange to be 15 microns in diameter as taught by Steffier for the purpose of providing fibers which exhibit excellent thermomechanical compatibility and creating a composite which is not initially micro-cracked (Col 2 Lns 49-56).
(xiv) Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier do not teach a diffusion coating applied to the surface of the ceramic matrix composite material wherein said diffusion coating increases crack initiation resistance.
(xv) Vu is also in the field of ceramic composites (see abstract) and teaches a diffusion coating (environmental barrier coating, see abstract) applied to a surface of a ceramic matrix composite (Introduction, first paragraph).
(xvi) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ceramic matrix composite material as taught by the combined teachings of Webb as modified by Farmer as further modified by Sudre as even further modified by Lange as even further modified by Steffier with the above aforementioned diffusion coating as taught by Vu for the purpose of providing a self-healing environmental barrier coating (see abstract) thereby increasing lifetime and reliability (Introduction, last sentence of paragraph 2).
(xvii) The Examiner is taking official notice that it is well known in the art for rotors of a high pressure compressor of a gas turbine engine to be an integrated blade rotor as evidenced by Stoyanov (integrated blade rotor 62, Fig 2; Col 4 Lns 51-52).
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Justin A Pruitt whose telephone number is (571)272-8383. The examiner can normally be reached T-F 8:30am - 6:30pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathaniel Wiehe can be reached at (571) 272-8648. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JUSTIN A PRUITT/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745
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