Shinya Miyaji

Interfacial state and characteristics of cold-sprayed copper coatings on aluminum substrate

Cold spray is a new process for bonding copper and aluminum. In this paper, the interfacial states of cold-sprayed copper on aluminum substrate were evaluated and compared with those resulting from hot extruding. No critical intermetallic layers were observed at the cold-sprayed interfaces and good electrical and mechanical properties were achieved. The effect of annealing on the characteristics of cold-sprayed bonding material was also examined. By annealing at appropriate temperature, a continuous layer of an intermetallic compound was formed and the electrical conductivity and bending strength were improved. This indicates that a good bonding state is obtained by using cold-spray technology in combination with subsequent thermal processing.