METHOD AND SYSTEM FOR EVALUATING QUALITY OF LASER BEAM WELDING

PROBLEM TO BE SOLVED: To provide a method and a system for evaluating a quality for evaluating, accurately and in real time, whether the joint with a welding bead is satisfactory or not when two stacked metal plates are irradiated with a laser beam for stack welding. SOLUTION: This method for evaluating the quality relates to the laser beam welding for welding two metal plates by shifting a welding torch 15 irradiating the laser beam along the surface of an upper metal plate 12 stacked on a lower metal plate 10. This method is composed of a detecting process and a judging process. In the detecting process, heat information is detected in at least one side of adjacent portions 42a, 43a on both sides of the fusion portion 41a on the surface of the upper metal plate in the welding. In the judging process, the width of the adjacent portion is obtained on the basis of the detected heat information to judge whether the joint is satisfactory or not by comparing the width with the pre-prepared reference value. COPYRIGHT: (C)2004,JPO