# US 5,705,271 A · Method for producing diamond coated member > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,271 A - Document ID: US5705271A - Status: Granted - Kind: A - Application number: 08/415,372 - Filed: 1995-04-03 - Granted: 1998-01-06 - Earliest claimed: 1994-04-01 - Assignees: Ngk Spark Plug Co., Ltd. - Inventors: Takashi Okamura; Takahisa Ushida; Satoshi Iio; Masakazu Watanabe - Web page: https://patentgrep.com/patent/US5705271A ## CPC - C23C 16/27: Diamond only - C23C 16/0209: {by heating} - C23C 16/0272: {Deposition of sub-layers, e.g. to promote the adhesion of the main coating} - C23C 16/279: {control of diamond crystallography} - C23C 28/04: only coatings of inorganic non-metallic material - C23C 28/048: {with layers graded in composition or physical properties} - C23C 30/005: {on hard metal substrates} - Y10T 428/24355: Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.] - Y10T 428/24479: including variation in thickness - Y10T 428/24942: including components having same physical characteristic in differing degree - Y10T 428/24983: Hardness - Y10T 428/30: Self-sustaining carbon mass or layer with impregnant or other layer - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Diamond coating member is produced by a method comprising a first coating step in which the first diamond coating layer is closely formed on fine irregularity parts of a substrate having fine irregularities substantially without void left between them and the fine irregularities is engaged with the above first layer to coat the above substrate, and a second coating step in which the surface of the first coating layer is coated with a second diamond coating layer comprising diamond having a higher wear resistance than that of the first coating layer. The diamond coating member is excellent in adhesion between the diamond coating layer and the substrate and has high durability without having the diamond coating layer scaled off by mechanical shocks. It has high wear resistance and enables mass production without fluctuation in product quality. ## Claims ### Claim 1 A diamond coated member comprising: a substrate, a first diamond coating layer which is directly deposited on and engaged with a part of the substrate having fine irregularities thereon, having substantially no voids left between the fine irregularities and the first diamond coating layer, said irregularities being sufficiently deep to provide engagement between the first diamond coating layer and the substrate, and a second diamond coating layer deposited on the first diamond coating layer comprising diamond having a higher wear resistance than that of the first coating layer. ### Claim 2 (depends on 1) The diamond coated member as defined in claim 1, wherein the second diamond coating layer comprises diamond of a high crystallinity. ### Claim 3 (depends on 1) The diamond coated member as defined in claim 1, wherein the part of said substrate having fine irregularities thereon comprises fine irregularities having an aperture diameter of 0.5 to 5 .mu.m, an aperture depth of 0.5 to 10 .mu.m and an aperture interval of 5 .mu.m or less. ### Claim 4 A diamond coated member obtained by the process comprising the steps of: a first coating step in which a first diamond coating layer is directly deposited on and engaged with a part of a substrate having fine irregularities formed thereon by a gas phase synthesis method in which a mixed gas comprising 80 to 93 volume % hydrogen, 0 to 2 volume % methane and 7 to 20 volume % carbon monoxide is reacted to deposit said first diamond coating layer directly on said substrate so that substantially no voids are left between the fine irregularities and the first diamond coating and so that said fine irregularities are sufficiently deep to provide engagement between the first diamond coating layer and the substrate; and a second coating step in which a second diamond coating layer comprising diamond of a higher wear resistance than the first diamond coating layer is deposited on a surface of the first diamond coating layer. ### Claim 5 A diamond coated member obtained by the process comprising the steps of: a first coating step in which a first diamond coating layer is directly deposited on and engaged with a part of a substrate having fine irregularities formed thereon by a gas phase synthesis method in which a mixed gas comprising 94 to 97 volume % hydrogen and 3 to 6 volume % carbon monoxide is reacted at a temperature of 800.degree. to 900.degree. C. to deposit said first diamond coating layer directly on said substrate so that substantially no voids are left between the fine irregularities and the first diamond coating and so that said fine irregularities are sufficiently deep to provide engagement between the first diamond coating layer and the substrate; and a second coating step in which a second diamond coating layer comprising diamond of a higher wear resistance than the first diamond coating layer is deposited on a surface of the first diamond coating layer. ### Claim 6 A diamond coated member obtained by the process comprising the steps of: a first coating step in which a first diamond coating layer is directly deposited on and engaged with a part of a substrate having fine irregularities formed thereon at a film forming rate of 0.1 to less than 1 .mu.m/h by a gas phase synthesis method in which a mixed gas comprising 94 to 97 volume % hydrogen and 3 to 6 volume % carbon monoxide is reacted at a temperature of 800.degree. to 900.degree. C. to deposit said first diamond coating layer directly on said substrate so that substantially no voids are left between the fine irregularities and the first diamond coating and so that said fine irregularities are sufficiently deep to provide engagement between the first diamond coating layer and the substrate; and a second coating step in which a second diamond coating layer comprising diamond of a higher wear resistance than the first diamond coating layer is deposited on a surface of the first diamond coating layer at a film forming rate of 1 to 2 .mu.m/h wherein the part of the substrate having fine irregularities formed thereon comprises fine irregularities having an aperture diameter of 0.5 to 5 .mu.m, an aperture depth of 0.5 to 10 .mu.m and an aperture interval of 5 .mu.m or less.