METHOD FOR WELDING METALLIC PLATE BY LASER, LASER-WELDED METALLIC PLATE, AND CASING STRUCTURE OF IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a welding method in which effect of the bubbles of evaporation components is eliminated that are produced in a plated area when welding is performed on a metallic plate coated with plating or the like on the surface. SOLUTION: This is a method for joining, by laser welding, a plurality of metallic plates 1, 2 having a coating with a surface treatment film. The method is characterized by preparing a hole or a notch 1a at a weld starting point at least on a first metallic plate to be irradiated with a laser beam, scanning the laser beam on a line connecting between the starting and ending points of welding, and joining the plural metallic plates along the line while the vapor of the surface treatment film is released from the hole or the notch.