# US 11,110,539 B2 · Methods and joints for welding sheets of dissimilar materials > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,110,539 B2 - Document ID: US11110539B2 - Status: Granted - Kind: B2 - Application number: 15/654,423 - Filed: 2017-07-19 - Published: 2018-02-08 - Granted: 2021-09-07 - Earliest claimed: 2016-08-05 - Assignees: Honda Motor Co., Ltd. - Applicants: Honda Motor Co., Ltd. - Inventors: Duane T. Detwiler; Timothy A. Abke - Web page: https://patentgrep.com/patent/US11110539B2 ## CPC - B23K 11/11: Spot welding - B23K 11/0026: {Welding of thin articles} - B23K 11/166: {of galvanized or tinned materials} - B23K 11/185: {of aluminium or aluminium alloys} - B23K 11/20: of different metals - B23K 26/361: for deburring or mechanical trimming (B23K26/351 takes precedence) - B23K 2101/006: {Vehicles} - B23K 2101/185: {Tailored blanks} - B23K 2101/34: Coated articles {; Surface treated articles} - B23K 2103/04: Steel {or steel} alloys - B23K 2103/10: Aluminium or alloys thereof - B23K 2103/20: Ferrous alloys and aluminium or alloys thereof - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM ## Abstract A method for welding a stack of sheets having a plurality of sheets of different materials is provided. In an aspect, the stack of sheets includes an aluminum sheet and a galvanneal steel sheet. In an aspect, the method includes resistively spot welding the galvanneal sheet to a hot-stamped steel sheet placed between the aluminum sheet and the galvanneal sheet, the sheet of hot-stamped steel including stress relief sections. The method further includes placing a metal foil on the aluminum sheet and vaporizing the metal foil to project portions of the aluminum sheet through the stress relief sections of the hot-stamped steel sheet to weld the portions of the aluminum sheet to the galvanized steel sheet. In another aspect, the method includes placing the metal foil on a raised portion of the aluminum sheet and projecting the raised portion of the aluminum onto the galvanneal steel sheet. ## Claims ### Claim 1 A method of performing welding, the method comprising: applying a current to a stack of sheets to resistively spot weld a first sheet of the stack of sheets to a second sheet of the stack of sheets, wherein the second sheet is a unitary vehicle structural component and includes at least two cut out sections, wherein applying the current to the stack of sheets comprises forming at least two spot welds between the first sheet and the second sheet; placing at least one metal foil on a first side of a third sheet of the stack of sheets; and vaporizing the at least one metal foil to project at least two portions of the third sheet through the at least two cut out sections of the second sheet to the first sheet to form welds between the first sheet and the third sheet, wherein the second sheet remains welded to the first sheet, and wherein the at least two spot welds alternate with the welds through the cut out sections to form a mechanical interlock between the first sheet, the second sheet, and the third sheet. ### Claim 2 (depends on 1) The method of claim 1, further comprising at least one of: removing a first coating from the first sheet; removing a second coating from the second sheet; or cladding the third sheet with a transition material. ### Claim 3 (depends on 1) The method of claim 1, wherein applying the current further comprises: applying the current to the stack of sheets to resistively spot weld a first side of the first sheet to a first side of the second sheet. ### Claim 4 (depends on 1) The method of claim 1, wherein vaporizing the at least one metal foil further comprises: forming the weld between the first side of the third sheet and a second side of the first sheet. ### Claim 5 (depends on 1) The method of claim 1, further comprising positioning one of the at least two cut out sections of the second sheet at an edge of the second sheet. ### Claim 6 A method of performing welding, the method comprising: applying a current to a stack of sheets to resistively spot weld a first sheet of the stack of sheets to a second sheet of the stack of sheets, wherein the second sheet is a unitary vehicle structural component and includes at least two cut out sections, wherein applying the current to the stack of sheets comprises forming at least two spot welds between the first sheet and the second sheet; placing at least one metal foil on a first side of a third sheet of the stack of sheets, wherein the third sheet is clad with a transition material; and vaporizing the at least one metal foil to project at least two portions of the third sheet through the at least two cut out sections of the second sheet to the first sheet to form welds between the first sheet and the third sheet, wherein the second sheet remains welded to the first sheet, and wherein the at least two spot welds alternate with the welds through the cut out sections to form a mechanical interlock between the first sheet, the second sheet, and the third sheet. ### Claim 7 (depends on 6) The method of claim 6, further comprising at least one of: removing a first coating from the first sheet; or removing a second coating from the second sheet. ### Claim 8 (depends on 6) The method of claim 6, wherein applying the current further comprises: applying the current to the stack of sheets to resistively spot weld a first side of the first sheet to a first side of the second sheet. ### Claim 9 (depends on 6) The method of claim 6, wherein vaporizing the at least one metal foil further comprises: forming the weld between the first side of the third sheet and a second side of the first sheet. ### Claim 10 (depends on 6) The method of claim 6, further comprising positioning the at least one cut out section of the second sheet at an edge of the second sheet. ### Claim 11 A vaporized foil actuator welding (VFAW) part, the part comprising: a first sheet of a stack of sheets resistively spot welded to a second sheet of the stack of sheets at a plurality of weld spots, wherein the second sheet is a unitary vehicle structural component and includes a plurality of cut out sections; and a third sheet of the stack of sheets welded to the first sheet through the plurality of cut out sections, wherein an alternation of the weld spots and welds in the plurality of cut out sections form a mechanical interlock. ### Claim 12 (depends on 11) The part of claim 11, wherein: the first sheet comprises a first type of steel, the second sheet comprises a second type of steel, and the third sheet comprises aluminum. ### Claim 13 (depends on 12) The part of claim 12, wherein: the first type of steel is a galvanneal steel, and the second type of steel is a hot-stamped steel.