Ultra-rapid transient liquid phase bonding of Mg alloys within 1 s in air by ultrasonic assistance

An ultra-rapid transient liquid phase bonding method was successfully used to join AZ31B Mg alloys by using pure Zn interlayers in air. The bonding time was shortened to 1 s with ultrasonic assistance. Eutectic structures, MgZn, and MgZn2 formed at relatively low temperatures of 360 °C and 370 °C. Only eutectic structures were observed at a high temperature of 380 °C because the entire joint was filled with eutectic liquid phase at this moment. MgZn2 had higher hardness and modulus than those of MgZn. The shear strength of joint was inversely proportional to its width. The joint fractured through MgZn2 at 360 °C and 370 °C, and through eutectoid structures at 380 °C. Keywords: Ultrasonic, Transient liquid phase, Intermetallic compound, Shear strength, Diffusion