Papers by Author: Jun Wang

Abstract: The lightest density of Mg has stimulated renewed interest in Mg based alloys for applications in the automotive, aerospace and communications industries. However, Mg in the pure form has relatively low strength, limited ductility and is susceptible to corrosion. Great efforts have been made to improve the mechanical properties of Mg alloys. Alloying Mg with other elements is one of the most important methods. An important class of Mg alloys is the Mg-Zn-RE system (RE = rare earth elements). In recent few decades, a series of new Mg-Zn-RE system alloys have been obtained, and detailed the structure and mechanical properties of the alloys. In this paper, the structure and mechanical properties of the Mg-Zn-RE alloys have been summarized. It showed that these alloys have high strength and they are prospected to be widely used in the future.

Abstract: The Mg-8Zn-8Al-4RE (RE = mischmetal, mass%) magnesium alloy was prepared by using casting method. The microstructure and mechanical properties of as-cast alloy, solid solution alloy and aged alloy samples have been investigated. Optical microscopy, X-ray diffractometery and scanning electron microscope attached energy spectrometer were used to characterize the microstructure and phase composition for the alloy. Net shaped τ-Mg32(Al,Zn)49 phase was obtained at the grain boundary, and needle-like or blocky Al11RE3 phase disperses in grain boundary and α-Mg matrix. The τ-Mg32(Al,Zn)49 phase disappeared during solution treatment and a new phase of Al2CeZn2 formed during subsequent age treatment. The mechanical properties were performed by universal testing machine at room temperature, 150 °C and 200 °C, separately. The ultimate tensile strength of as-cast alloy is lower compared to an age treatment alloy at 200 °C for 12h. The strengths decreased with enhancing test temperature, but elongation has not been effect by age treatment.