Microstructure, mechanical and degradation properties of equal channel angular pressed pure magnesium for biomedical application

Abstract

Magnesium is a biocompatible and biodegradable metal, which has attracted much interest in biomedical engineering. Pure magnesium shows the low strength and plasticity at ambient temperature. Microstructure, mechanical properties and degradation properties of the equal channel angular pressed pure magnesium have been investigated for biomedical application in detail by optical microscopes, mechanical properties testing and corrosion testing. The results have revealed that the processing temperature and routes are important factors that affect the properties of pure Mg by equal channel angular pressing. The two-step equal channel angular pressing processing (one pass at 360°C and three passes at 200°C) has been successfully applied to control the microstructure, mechanical and degradation properties of the pure Mg. Optical microscopy observation has indicated that the grain size of the as cast pure magnesium has been significantly decreased after equal channel angular extrusion, which has mainly contributed to the high tensile strength and good elongation. Equal channel angular pressed pure magnesium has provided moderate corrosion resistance, which has opened a new window for materials design, especially for biomedical.