| 摘要 |
PURPOSE:To extend considerably the life of electrode tips in the spot welding stage of materials to be welded by the electrode tips by sticking Al to a specific thickness on the surfaces of the electrode tips in contact with the materials. CONSTITUTION:Galvanized steel sheets 1, 2 having galvanized layers 3 are partially superposed and the electrode tips 5, 6 are disposed on the superposed parts in contact therewith. Electricity is then conducted to the tips 5, 6 to spot-weld the sheets 1, 2. Al or Al alloys 7, 8 are preliminarily stuck to >=0.8mu onto the surfaces of the tips 5, 6 in contact with the sheets 1, 2. The alloys 7, 8 which consist essentially of Al and are added with 1 or >=2 kinds among about 3-40% Si, about 1-10% Cu, about 0.1-5% Mg and about 0-3% Mn in combination are preferable. The Zn-Al alloy is thus positively formed on the surfaces of the tips 5, 6 and the life thereof is improved. |
