| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve formability wherein concentration of strain towards a low strength material side or a thin board side can be reduced. SOLUTION: This method is referred to a sheet of blank material comprising a thick board 13, a thin board 11 and another board 12 inserted in between the two, wherein they are all welded together by a laser respectively. The blank material is press formed into an inner panel of a door for a vehicle. At this time, the thick board 13 and a laser welded position inserted in between are arranged at an outer side from a corner R of a shrinkage flange formed portion 11.</p> |
