抄録
Although Al alloy-pure Cu joints have been produced by the conventional welding method, some combination cannot be joined with high efficiency. The efficiency is considered to be reduced by the formation of intermetallic compounds and the involvement of metal flake in the joint specimens. The present study examined an A2017 Al alloy-Cu joint formed by a new friction welding technology, in which an intermediate material is inset for friction between joint specimens. The optimal welding were determined by thermal elastic-plastic stress analysis. The joints formed by the new technology exhibited the following features: (1) a maximum joint efficiency of 60% (versus 50% in the conventional process); (2) no intermetallic compounds or metal flake involvement ( as observed under scanning electron microscopy); (3) increased oxygen content at the Al side near the interface, but marginal increase at the Cu side. We also determined the precise position of the welding interface based on the change in oxygen content near the interface. To produce robust joints using this combination of materials, both materials should be plastically deformed by maintaining the strength balance between Al and Cu near the interface.
