METHOD FOR PRODUCING ELECTRICAL-RESISTANCE SPOT-WELDED JOINTS

Abstract

The present disclosure provides a method for producing an electrical resistance spot welded joint with superior nugget diameter stability.In test welding, the preliminary current passage and the main current passage are performed with constant current control in two or more patterns, the preliminary current passage is performed under the same current passage condition and an electrode force of less than 2.5 kN, an electrical property between the electrodes in the preliminary current passage and a time variation curve of an instantaneous amount of heat generated per unit volume during the main current passage are stored, in actual welding, the preliminary current passage is performed with constant current control under the same current passage condition as the preliminary current passage of the test welding, a target in the main current passage in the actual welding is set by a comparison of an electrical property between the electrodes in the preliminary current passages, and adaptive control welding is performed to control a number of current passages as the main current passage.