Effect of Temperature on Interface Microstructure and Mechanical Properties of AZ31/Al/Ta Composites Prepared by Vacuum Hot Compression Bonding

Abstract:

AZ31/Al/Ta composites were prepared using the vacuum hot compression bonding (VHCB) method. The effect of hot compressing temperature on the interface microstructure evolution, phase constitution, and shear strength at the interface was investigated. Moreover, the interface bonding mechanisms of the AZ31/Al/Ta composites during the VHCB process were explored. The results demonstrate that as the VHCB temperature increases, the phase composition of the interface between Mg and Al changes from the Mg-Al brittle intermetallic compounds (Al₁₂Mg₁₇ and Al₃Mg₂) to the Al-Mg solid solution. Meanwhile, the width of the Al/Ta interface diffusion layer at 450 °C increases compared to that at 400 °C. The shear strengths are 24 and 46 MPa at 400 and 450 °C, respectively. The interfacial bonding mechanism of AZ31/Al/Ta composites involves the coexistence of diffusion and mechanical meshing. Avoiding the formation of brittle phases at the interface can significantly improve interfacial bonding strength.