# US 10,309,004 B2 · Metal sheet and method for its treatment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,004 B2 - Document ID: US10309004B2 - Status: Granted - Kind: B2 - Application number: 14/802,453 - Filed: 2015-07-17 - Published: 2016-01-21 - Granted: 2019-06-04 - Earliest claimed: 2014-07-18 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Hartmut Baumgart; Ronald Sanders - Web page: https://patentgrep.com/patent/US10309004B2 ## CPC - C23C 10/28: using solids, e.g. powders, pastes - B41M 7/009: {using thermal means, e.g. infrared radiation, heat} - C23C 8/04: Treatment of selected surface areas, e.g. using masks - C23C 8/66: of ferrous surfaces - C23C 8/72: more than one element being applied in one step - C23C 10/04: Diffusion into selected surface areas, e.g. using masks - C23C 10/60: After-treatment - B41M 1/10: Intaglio printing {; Gravure printing} - B41M 1/12: Stencil printing; Silk-screen printing - 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) - B41M: PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING, (correction of typographical errors B41J; processes for applying transfer pictures or the like B44C1/16; fluid media for correction of typographical errors by coating C09D10/00; printing textiles D06P) ## Abstract A method for treating sheet metal is disclosed in which a material containing at least one alloying element is applied onto a first area of at least one surface of the metal sheet. A second area of the surface is kept free of the material. The metal sheet is subsequently heat treated in order to diffuse the alloying element into the first area of the metal sheet. The temperature of the first area is lower than the melting temperature of the metal sheet during the diffusion. ## Claims ### Claim 1 A method for processing a metal sheet to create a product of a designated shape, the method comprising: identifying, based on load characteristics of the product a load area of the product that is configured to carry a load; applying a material, as a number of separated strips, onto a first area of a surface on the metal sheet such that a second area of the surface is kept free of the material, wherein the material contains at least one alloying element; subsequent to the application of the material, heat-treating the metal sheet such that the alloying element diffuses into the first area of the metal sheet; and forming the metal sheet into the designated shape with the first area corresponding to the load area. ### Claim 2 (depends on 1) The method according to claim 1, wherein the heat treatment is carried out in a furnace configured to promote diffusion of the alloying element from the material into the first area, without diffusion of the material into the second area. ### Claim 3 (depends on 1) The method according to claim 1, wherein the forming comprises forming the metal sheet in a forming tool into a final cross section of the product; and further comprising cooling the metal sheet during a cooling phase that follows the heat-treating, without reheating of the metal sheet after the heat-treating. ### Claim 4 (depends on 3) The method according to claim 3, wherein the forming and cooling comprises cooling the metal sheet through contact with the forming tool. ### Claim 5 (depends on 1) The method according to claim 1, wherein the material is applied to the metal sheet by a process selected from the group consisting of gravure printing, screen printing, or spraying. ### Claim 6 (depends on 1) The method according to claim 1, wherein the material is applied wet, and further comprising stacking a plurality of blanks of the metal sheet before the material has dried; and transferring the material from the surface to an adjacent one of the blanks by contact. ### Claim 7 A method for treating sheet metal to form a product from a metal sheet, the method comprising: identifying a first area of the metal sheet intended to correspond to a load area of the product, said load area having a higher load characteristic than a second area of the product and configured to carry a load; applying a material, as a number of separated strips which comprise the first area, onto a surface of the first area such that a second area of the surface is kept free of the material, wherein the material contains at least one alloying element; subsequent to application of the material, heat-treating the metal sheet such that the alloying element diffuses into the first area of the metal sheet; forming the metal sheet into a final cross section of the product via roll forming the metal sheet by passing the metal sheet in a longitudinal direction through profiled roll pairs, wherein the separated strips extend in the longitudinal direction, and resulting in the first area corresponding to the load area; and continuously cooling the metal sheet during the forming by contact with the profiled roll pairs. ### Claim 8 (depends on 7) The method according to claim 7, comprising: preparing the metal sheet to join with an attachment part; and matching a first standard potential of the first area with a second standard potential of the attachment part by selection of the alloying element to minimize contact corrosion when the first area contacts the attachment part.