ALUMINUM COPPER CLAD MATERIAL

摘要

An aluminum copper clad material has excellent bonding strength and includes an aluminum layer and a copper layer that are bonded without a nickel layer interposed therebetween. The aluminum layer and the copper layer are diffusion-bonded via an Al—Cu intermetallic compound layer. The copper layer satisfies Dcs≦0.5×Dcc, where Dcc represents the average crystal grain size of crystal grains in a central portion in the thickness direction of the copper layer, and Dcs represents the average crystal grain size of an interface adjacent portion C2 in the copper layer that is about 0.5 μm apart from the interface between the copper layer and the intermetallic compound layer. The intermetallic compound layer has an average thickness of about 0.5 μm to about 10 μm.

主权项

1. A method for producing an aluminum copper clad material in which an aluminum layer and a copper layer are diffusion-bonded via an Al—Cu intermetallic compound layer, the method comprising the steps of:
preparing an aluminum plate that serves as a source of the aluminum layer and a copper plate that serves as a source of the copper layer; pressure-welding the aluminum plate and the copper plate that are stacked on each other; and diffusion-annealing the resulting pressure-welded material; wherein the copper plate satisfies Hc≧1.6×Hca, where Hc (Hv) represents an average surface hardness of a surface on a pressure-welded side of the copper plate, and Hca (Hv) represents an average surface hardness of a completely annealed material of the copper plate; and the diffusion annealing is carried out at an annealing temperature T(° C.) of about 150° C. to about 550° C. for an annealing time t(min) in a range satisfying the following expressions:
tmin≦t≦tmaxtmax=−1.03×T+567tmin=0.5, when −0.19×T+86<0.5,tmin=−0.19×T+86, when −0.19×T+86≧0.5.