| 摘要 |
PURPOSE:To weld different kind of metals which are so far thought to be impossible to weld because of difference in melting point easily and obtain a weldment of high quality in spot welding method that applies current to a pressure welding point of welded metals of different kind held on a pair of holders, by applying current twice as specified. CONSTITUTION:For instance, a tungsten rod 5, and a copper and chrome copper 10 are held respectively on holders 1, 6. These are contacted and pressed, and welded by applying current to joint plane by a welding control circuit 11. In the first step, current is applied by relatively small quantity of electricity, and then in the second step current is applied by larger quantity of electricity than the first step. Thus, welding of a tungsten rod 5 and copper and chrome copper 10 which so far made by brazing around the joint plane is made possible. Labor for brazing work can be saved, and bad influences caused by rise of temperature of brazing filler metal and change of resistance of brazing are not given to the weldment, and quality of welding is not lowered. |
