Ultrasonic effect mechanism on transient liquid phase bonding joints of SiCp reinforced Mg metal matrix composites using Zn-Al-Zn multi-interlayer.

The effect of ultrasound on transient liquid phase bonding of SiCp reinforced Mg metal matrix composites was investigated based on microstructure evolution, phase composition, SiC particles redistribution, mechanical properties and fracture path of the bonded joint. The results indicate the joint of full solid solution without SiC particles aggregation was obtained by inducing the secondary ultrasonic-assisted holding process at 430 °C for 30 s and the joint shear strength reach to 175.5 MPa (87.5% base material strength). The time needed for the isothermal solidification process was significantly shortened to several second time, which is mainly ascribed to the ultrasonic vibration can squeeze out a large fraction of residual liquid phase and facilitate the atomic diffusion in grain boundary.