LASER LAP WELDING JOINT, METHOD FOR MANUFACTURING LASER LAP WELDING JOINT, AND STRUCTURE MEMBER FOR AUTOMOBILE BODY

• Main Authors: ASHIDA HAJIME, NAITO YASUAKI, MATSUI SHO, FUJIMOTO HIRONORI
• Format: Patent
• Language: English; Japanese
• Published: 23.06.2023
• Subjects: ALLOYS; CHEMISTRY; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; FERROUS OR NON-FERROUS ALLOYS; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METALLURGY; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WELDING; WORKING BY LASER BEAM

To provide a laser lap welding joint capable of suppressing welding cracks at a bead tail end, a method for manufacturing the same, and a structure member for an automobile body.SOLUTION: The laser lap welding joint comprises; a plurality of metal plates; and a first bead that is a linearly extending laser welding part. The ratio G/T of a total value G of sizes of gaps among the metal plates to a total value T of thicknesses of the metal plates is 0-18%. The length L1 of the first bead is 10-100 mm. The laser lap welding joint further comprises a second bead. The length L2 of the second bead is shorter than the length L1. In a tail end surrounding region, the length of a region of the second bead having a distance of 2 mm or shorter from the width end of the first bead is 2 mm or shorter along the center axis of the first bead. The second bead is isolated from the center axis of the first bead. The second bead is not included in a start end surrounding region.SELECTED DRAWING: Figure 1 【課題】ビード終端部における溶接割れを抑制可能な重ねレーザ溶接継手、重ねレーザ溶接継手の製造方法、及び自動車車体用構造部材を提供する。【解決手段】本発明の一態様に係る重ねレーザ溶接継手は、複数の金属板と、線状に延在するレーザ溶接部である第１のビードとを備え、複数の金属板の隙間の大きさの合計値Ｇと、複数の金属板の厚さの合計値Ｔとの比率Ｇ／Ｔが０～１８％であり、第１のビードの長さＬ１が１０～１００ｍｍであり、重ねレーザ溶接継手がさらに第２のビードを有し、第２のビードの長さＬ２がＬ１より小さく、終端周辺領域において、第２のビードにおける、第１のビードの幅方向の端部からの距離が２ｍｍ以下である領域の長さが、第１のビードの中心軸に沿って２ｍｍ以上であり、第２のビードは第１のビードの中心軸から離隔され、始端周辺領域に第２のビードが含まれない。【選択図】図１