| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide laser beam welding method of a high-strength steel sheet, the welding method achieving reduction in cracks in the weld zone of a lapped part. <P>SOLUTION: The laser beam welding method of a high-strength steel sheet includes: overlapping a plurality of the steel sheets one on another; irradiating the upper surface of the uppermost steel sheet of the lapped part with laser beam; and performing welding while melting the lapped part to the lower surface of the undermost steel sheet, wherein welding is performed by supplying shield gas having a dew point of 15°C or under to the upper surface and the lower surface of the overlapped part in the vicinity of the molten zone. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
