| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem that an electrode for the present resistance welding is only a lump of a copper alloy (an electrode material), and cannot resist the deposition wear in the resistance welding of a galvanized steel sheet. <P>SOLUTION: Deposition wear is caused by alloying between zinc and copper. When a heated portion of an electrode is rapidly cooled, the wear is reduced. The wear is executed from a surface layer part at a fore end of the electrode. In an instantaneous view, all of the remaining portion of the electrode functions as a chiller. Copper is optimum for the chiller. On the other hand, the entire electrode cannot be made of copper. The entire remaining portion except the portion (core) to be consumed by the wear can be reasonably formed of copper. The composite electrode is an electrode more than the conventional one. In the solid electrode, an electrode material with inferior cooling capacity is applied to the section which is originally formed of copper. The electrode has a structure in which the wear of the core is intentionally accelerated. When the deposition resistance of the electrode material is enhanced, the electric conductivity is generally degraded, and the function of the electrode material is lost. Disqualification as the electrode material does not necessarily mean the disqualification of a core material. When the core is formed of the electrode material and surrounded by copper, the disqualification is solved. <P>COPYRIGHT: (C)2013,JPO&INPIT |
