METHOD FOR LASER WELDING OF MATERIALS WITH DIFFERENT THICKNESSES AND WELDED MEMBER HAVING DIFFERENT THICKNESSES PRODUCED BY SAID METHOD

摘要

Provided is a laser welding method of materials having different thicknesses that can achieve excellent weld strength regardless of the thickness of a thick plate, and a welded member having different thicknesses. That is, the present invention is characterized by a laser welding method of materials having different thicknesses, including: abutting two plates (10), (12) having different thicknesses such that one surface of the plate (10) and one surface the plate (12) are made flush with each other; and thereafter welding the plates (10), (12) by applying a laser beam (14) to abutting surfaces thereof, wherein the laser beam (14) is made incident obliquely from the flush surface of the thin plate (10) toward an abutting end face (12a) of the thick plate (12), a target position (P) of the laser beam (14) is set on the abutting end face (12a) of the thick plate (12), and a target position depth D in the plate from a surface thereof on the incident side of the laser beam (14) is set within a range of the following expression (1), t/3 ‰¤ D ‰¤ t ...(1) (where t is a thickness, in a planar direction, of an abutting end face (10a) of the thin plate (10), and D and t are both given in mm).