Microstructure and Mechanical Properties of Medical Magnesium Alloy Fabricated by Unequal Channel Angular Pressing

Xiaoping Luo, Mingang Zhang, Daqin Fang, Yaosheng Chai

School of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan, China.
School of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan, China..

DOI: 10.4236/jbnb.2013.42018                

Abstract

A new unequal channel angular pressing (UCAP) procedure is proposed for ultrafine-grained metals and alloys. The microstructures and mechanical properties of Mg-5.8Zn-1.2Y-0.7Zr alloys subjected to unequal channel angular pressing (UCAP) are investigated. It is found that the optimum condition in UCAPed alloy is obtained at 523 K with a largest elongation to failure of 13.1% and ultimate tensile strength of ~400 MPa. Microstructural observations show that the grain size is refined to ~1.0 μm during UCAP. The probable mechanisms for these high mechanical properties are attributed to grain size and destroyed secondary phase strengthening effects and fine precipitates formed during pressing at high temperature by severe shear and plastic deformation.

Keywords

Mg-Zn-Y-Zr Magnesium Alloy; Unequal Channel Angular Pressing; Microstructure; Mechanical Property

Conflicts of Interest

The authors declare no conflicts of interest.

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