METHOD FOR LASER WELDING OF ABUTTED PART HAVING ZINC PLATED LAYER

摘要

PROBLEM TO BE SOLVED: To improve the good appearance of a weld bead and to form a smooth faced welding bead which smoothly continues into the zinc plated layer in the vicinity of a weld zone. SOLUTION: The method for a laser welding of a batted part having a zinc plated layer which is characterized by the fact that a filler wire is fed to a molten pool at a laser welding zone or its vicinity when the abutted part having a zinc plated layer is welded with a laser beam. The filler wire has excellent wettability to zinc when melted, has a melting point lower than that of a steel material covered with a zinc plated layer and includes compositions of which the melting points are close to that of zinc. The laser beam used is a YAG laser beam. The abutted part is a facial abutted part of the zinc plated layer of two galvannealed steel plates or the corner of crossing of the zinc plated layer of a galvannealed steel plate and the zinc plated layer of the other galvannealed steel plate of which the end face is abutted to the zinc plated layer.