# US 5,707,748 A · Coated tool with increased service life > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,707,748 A - Document ID: US5707748A - Status: Granted - Kind: A - Application number: 08/623,511 - Filed: 1996-03-28 - Granted: 1998-01-13 - Earliest claimed: 1993-07-21 - Assignees: Balzers Aktiengesellschaft - Inventors: Erich Bergmann - Web page: https://patentgrep.com/patent/US5707748A ## CPC - C23C 14/0635: {Carbides} - C23C 14/06: characterised by the coating material ({C23C14/0021} , C23C14/04 take precedence) - C23C 14/0641: {Nitrides (C23C14/0617 takes precedence)} - C23C 14/0664: {Carbonitrides} - Y10T 428/24967: Absolute thicknesses specified - 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 A tool with at least one area which is to be exposed to wear, is coated in a vacuum process with a first hard coating lying directly on the tool material and a superimposed exterior friction reducing layer over the hard coating. The grain size of the hard and friction reducing layers has a linear average width of less than 1 .mu.m. ## Claims ### Claim 1 A tool comprising a tool body with at least one area to be exposed to wear and a coating on at least the area to be exposed to wear, which is coated by a vacuum procedure, the coating consists essentially of at least one hard layer lying directly on the tool body, and at least one superimposed exterior friction reducing layer on the hard layer, the friction reducing layer being a mixture of metal carbide and carbon, and being made so as to be free of any halide, a grain size of the hard and friction reducing layers have a linear average width of less than 1 .mu.m, the friction reducing layer also having a lower thickness than the hard layer. ### Claim 2 (depends on 1) A tool according to claim 1, wherein the grain size of the friction reducing layer is less than 0.1 .mu.m. ### Claim 3 (depends on 2) A tool according to claim 2, wherein the hard layer has a compressive internal stress of more than 0.2 Gigapascal. ### Claim 4 (depends on 2) A tool according to claim 2, wherein the tool is for cutting and forming of metal and plastics, and the hard layer consists essentially of at least one of: a metal carbide; a metal nitride; a metal carbonitride of titanium, hafnium and zirconium; and alloys thereof with other metals. ### Claim 5 (depends on 4) A tool according to claim 4, wherein a carbon share of the friction reducing layer is more than 61 at%. ### Claim 6 (depends on 5) A tool according to claim 5, wherein the metal carbide of the friction reducing layer, consists essentially of at least one of: chromium; and wolfram. ### Claim 7 (depends on 4) A tool according to claim 4, wherein the friction reducing layer has a thickness of about 1/3 that of the hard layer, and is about 0.12 .mu.m to 1.6 .mu.m. ### Claim 8 (depends on 4) A tool according to claim 4, wherein the hard layer has a layer thicknesses ranging from about 1.1 .mu.m to 8 .mu.m. ### Claim 9 (depends on 2) A tool according to claim 2, wherein the hard layer consists essentially of one of TiN and (TiAlV.sub.6)N, and the friction reducing layer consisting essentially of one of CrC/C and WC/C. ### Claim 10 (depends on 9) A tool according to claim 9, wherein the friction reducing layer has a thickness of about 1/3 that of the hard layer, and is about 0.12 .mu.m to 1.6 .mu.m. ### Claim 11 (depends on 9) A tool according to claim 9, wherein the hard layer has a layer thickness ranging from about 1.1 .mu.m to 8 .mu.m. ### Claim 12 (depends on 2) A tool according to claim 2, wherein the hard layer is TiN and the friction reducing layer is WC/C. ### Claim 13 (depends on 1) A tool according to claim 1, wherein the tool body is for cutting and forming metals and plastics, the carbon share of the friction reducing layer being more than 61 at%. ### Claim 14 (depends on 13) A tool according to claim 13, wherein the metal carbide of the friction reducing layer consists essentially of at least one of: chromium; and wolfram. ### Claim 15 (depends on 14) A tool according to claim 14, wherein the hard layer consists essentially of at least one of: a metal carbide; a metal nitride; a metal carbonitride of titanium, hafnium, and zirconium; and alloys thereof with other metals. ### Claim 16 A tool comprising tool body with at least one area to be exposed to wear and a coating on at least the area to be exposed to wear, which is coated by a vacuum procedure, the coating consisting essentially of at least one hard layer lying directly on the tool body, the hard layer having a compressive internal stress of more than 0.2 Gigapascal, and at least one superimposed exterior friction reducing layer on the hard layer, the friction reducing layer being a mixture of metal carbide and carbon, a grain size of the hard and friction reducing layers have a linear average width of less than 0.1 .mu.m, the friction reducing layer having a thickness that is less than that of the hard layer, and being about 0.12 .mu.m to 1.6 .mu.m, the hard layer consisting essentially of at least one of, a metal carbide; a metal nitride, a metal carbonitride of titanuim, hafnium, and zirconium; and alloys thereof with other materials; the friction reducing layer, consisting essentially of one of CrC/C and WC/C, and being made so as to be free of any halide. ### Claim 17 A tool comprising a tool body with at least one area to be exposed to wear and made by the process comprising coating the one area to be exposed to wear with at least one hard layer lying directly on the tool body in a vacuum process, and superimposing on the hard layer an exterior friction reducing layer using physical vapor deposition in the vacuum process, the friction reducing layer being a mixture of metal carbide and carbon, and being made to be free of any halide, a grain size of the hard layer and the friction reducing layer having a linear average width of less than 1 .mu.m, the friction reducing layer also having a lower thickness than the hard layer, the coating on the at least one area of the tool which is exposed to wear consisting essentially of the at least one hard layer and the at least one superimposed exterior friction reducing layer.