# US 4,400,408 A · Method for forming an anticorrosive coating on a metal substrate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,400,408 A - Document ID: US4400408A - Status: Granted - Kind: A - Application number: 06/263,542 - Filed: 1981-05-14 - Granted: 1983-08-23 - Earliest claimed: 1980-05-14 - Assignees: Permelec Electrode Ltd. - Inventors: Hiroshi Asano; Takayuki Shimamune; Toshiki Goto; Hideo Nitta; Masashi Hosonuma - Web page: https://patentgrep.com/patent/US4400408A ## CPC - C23C 24/106: {Coating with metal alloys or metal elements only} - B22F 7/04: with one or more layers not made from powder, e.g. made from solid metal - C23C 18/143: {Radiation by light, e.g. photolysis or pyrolysis} - C23C 18/145: {Radiation by charged particles, e.g. electron beams or ion irradiation} - C23C 24/08: by application of heat or pressure and heat (C23C24/04 takes precedence) - 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) - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER ## Abstract A method for forming an anticorrosive coating on the surface of a metal substrate, which comprises, in one embodiment, (1) coating the surface of the metal substrate with an anticorrosive metal capable of forming an alloy with the substrate metal and/or a hydride of the anticorrosive metal; (2) heating the coated surface, and then; (3) heating the coated surface in a vacuum or in an atmosphere substantially inert to the metal coating and the metal substrate by irradiating the coated surface with electron beams, laser beams or a plasma arc to sinter the coated metal and form an alloy layer in the interface between the metal substrate and the metal coating and, in another embodiment, subsequent to Step (2) and prior Step (3) above, coating the coated surface with a solution of a thermally decomposable platinum-group metal compound and then heating the resulting coated surface at about 40.degree. C. to about 600.degree. C. ## Claims ### Claim 1 A method for forming an anticorrosive coating on the surface of a metal substrate, which comprises: (1) coating the surface of the metal substrate with a powder of an anticorrosive metal capable of forming an alloy with the substrate metal and/or a hydride of the anticorrosive metal; (2) heating the coated surface; and then (3) heating the coated surface in a vacuum or in an atmosphere substantially inert to the metal coating and the metal substrate by irradiating the coated surface with electron beams or a plasma arc to sinter the coated metal and form an alloy layer only in the interface between the metal substrate and the metal coating. ### Claim 2 A method for forming an anticorrosive coating on the surface of a metal substrate, which comprises: (1) coating the surface of the metal substrate with a powder of an anticorrosive metal capable of forming an alloy with the substrate metal and/or a hydride of the anticorrosive metal; (2) heating the coated surface; (3) coating the coated surface with a solution of a thermally decomposable platinum-group metal compound; (4) heating the resulting coated surface at about 40.degree. C. to about 600.degree. C.; and then (5) heating the coated surface in a vacuum or in an atmosphere substantially inert to the metal coating and the metal substrate by irradiating the coated surface with electron beams or a plasma arc to sinter the coated metal and form an alloy layer only in the interface between the metal substrate and the metal coating. ### Claim 3 (depends on 1, 2) The method as in claim 1 or 2, wherein after irradiation with the electron beams or plasma arc, the method includes subjecting the coated surface to a rolling treatment. ### Claim 4 (depends on 3) The method as in claim 3, wherein after said rolling treatment, the method includes heating the coated surface by irradiating the coated surface with electron beams or a plasma arc. ### Claim 5 (depends on 1, 2) The method as in claim 1 or 2, wherein the metal substrate is titanium, tantalum, zirconium, niobium or an alloy composed mainly of these metals. ### Claim 6 (depends on 1, 2) The method as in claim 1 or 2, wherein the metal substrate is iron, nickel, cobalt, copper, or an alloy composed mainly of these metals. ### Claim 7 (depends on 1, 2) The method as in claim 1 or 2, wherein the anticorrosive metal and/or the hydride of the metal is selected from the group consisting of tantalum, zirconium, niobium, titanium, molybdenum, tungsten, vanadium, chromium, nickel, silicon and hydrides thereof. ### Claim 8 (depends on 2) The method as in claim 2, wherein the platinum-group metal compound is selected from the group consisting of halogen-compounds of and organic compounds of platinum, iridium, ruthenium, palladium and rhodium, and mixtures thereof. ### Claim 9 (depends on 1, 2) The method as in claim 1 or 2, wherein the irradiation of the surface with electron beams or a plasma arc is with an intensity sufficient to form said alloy layer only in the interface between said metal substrate and said metal coating.