| 摘要 |
PROBLEM TO BE SOLVED: To realize direct joining of different kinds of metals by heating vacuum rolling. SOLUTION: When two sheets of different kinds of metals 4, 5 are heated in a vacuum and are rolled lapped together, a joining surface of the metal 4 of one of the different metals is subjected to surface treatment in association with roughness. It is effective to execute surface treatment also on the joining surface of the other metal 5 in association with roughness. The roughness is preferably <=3.0 S after surface treatment, and is further preferably <=2.2 S. In the direct joining of aluminum alloy and welding carbon steel for structure, the roughness of both the joining surfaces is above all preferably <=2.2 S. Considering from the nature of rolling joining by which increase in joining area and wedge effect joining or others by rugged fitting are expected, it was considered that it was preferable at the beginning that surface roughness is big to some extent, but direct joining becomes possible by suppressing the roughness within an upper limit. |
