Effects of ultrasonic vibration on solidification structure and properties of Mg-8Li-3Al alloy

Ultrasonic vibration was introduced into the Mg-8Li-3Al alloy melt during its solidification process. The microstructure, corrosion resistance and mechanical properties of the Mg-8Li-3Al alloy under ultrasonic vibration were investigated. The experiment results show that the morphology of a phase is modified from coarse rosette-like structure to fine globular one with the application of ultrasonic vibration. The fine globular structure is obtained especially when the power is 170 W, and the refining effect also gets better with prolonging the ultrasonic treatment time. The corrosion resistance of the alloy with 170 W of ultrasonic vibration for 90 s is improved apparently compared with the alloy without ultrasonic vibration. The mechanical properties of alloys with ultrasonic vibration are also both improved apparently. The tensile strength and elongation of alloy improve by 9.5% and 45.7%, respectively, with 170 W of ultrasonic treatment for 90 s.