Effect of aging treatment on bonding interface properties of hot-pressed Cu/Al clad material

This paper dealt with the interfacial bonding properties of Cu/Al clad materials by the variation of aging treatment times. Cu/Al clad materials were fabricated by a hot-pressing process. A subsequent heat treatment was also performed for the interfacial strengthening of Cu/Al clad materials. The characterization of Cu/Al clad materials was evaluated by means of OM, SEM, EDX and Knoop hardness test. Several diffusional layers were created at the interfacial region of Cu/Al clad materials, due to the chemical reaction of Cu and Al elements. The thicknesses of interfacial diffusion layers for Cu/Al clad materials increased with the increase of aging treatment time, accompanying the variation of intermetallic compounds. The hardness strengthening of diffusion layers by the increase of aging treatment time was also affected by the formation of η 2 phase at the bonding interfacial region.