METHOD FOR LASER BEAM WELDING OF SHOCK-ABSORBING MEMBER HAVING EXCELLENT SHOCK ABSORPTION CHARACTERISTIC AGAINST AXIAL COLLAPSE

摘要

PROBLEM TO BE SOLVED: To prevent a break of welded metal and to obtain an excellent shock absorption characteristic. SOLUTION: In the method for welding with a laser beam a steel palate 1 having a hat-shaped cross section which forms a shock absorption member having a closed cross sectional structure and a flat steel plate 2 or a steel plate having a hat-shaped cross section at the flange parts 3 of the steel plate having a hat-shaped cross section, the welding is continuously performed in a way that the width Wb of molten zone on the lapped face of the flange part is set at >=1.4 and <=3.0 times the plate thickness t.