| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a welding method where solidification cracks in overlap laser welding is prevented. <P>SOLUTION: In the laser welding method where a plurality of sheet materials are overlapped, and, as laser light is emitted to the vicinities of the edge parts of the overlapped sheet materials from the overlapping direction in such a manner that melting is caused to the back face of the overlapped material on the lower side, the laser light is moved along the edge parts, so as to form a weld zone, and the overlapped sheet materials are mutually welded, at least one sheet material in the plurality of sheet materials is made of a high tensile strength steel, and further, the weld zone has a weld metal comprising, C<0.05% and P+S<0.03%, or by mass, 0.08%<C<0.7% and P+S<0.05%. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
