Effect of Bonding Time on Microstructure and Mechanical Properties of AZ31/Zn/Sn/5083 Diffusion-Bonded Joints
摘要
Diffusion bonding of AZ31 magnesium alloy and 5083 aluminum alloy with Zn/Sn as the interlayer was carried out. By synergistically adjusting the Zn-Sn eutectic reaction time and the bonding time, a consistent thickness of residual Zn interlayer was maintained. The results showed that the MgZn2 layer exhibited a distinct preferred orientation along the rolling direction. This preferred orientation was enhanced with time, accompanied by significant grain coarsening and the average MgZn2 grain size increasing from 5.6 to 9.8 μm. The MgZn2 layer also showed the highest microhardness of 365 HV. The shear strength of the joint peaked at 29.6 MPa at the bonding time of 120 min. As the bonding time increased, the fracture mode evolved from brittle cleavage fracture to ductile fracture, and finally to brittle intergranular fracture.