| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for spot-welding an aluminum-plated steel sheet, which enables elongation of the life of welded spots, and does not require frequent polishing operations for an electrode tip. SOLUTION: In this method of spot welding, a pair of aluminum-plated steel sheets or a pair of an aluminum-plated steel sheet and another metal sheet are overlapped with each other as members to be welded. The sheets are nipped and pressed by means of a pair of electrode tips. The welding portions of the members to be welded are fused by the Joule's heat generated by supplying an electric current between the electrode tips. After that, nuggets are formed by cooling and solidifying the welding portions by interrupting the electric current. In this case, a down-slope process for gradually reducing the electric current after fusing the welding spot is provided in order to lower the cooling speed of the welding portion by reducing the heat conduction from the welding portion to the electrode tip. COPYRIGHT: (C)2006,JPO&NCIPI |
