Mechanical and electrochemical properties of friction stir processed magnesium alloy AZ31 for biomedical applications: A pilot study

Abstract

Although having suitable mechanical properties, the high corrosion and resorption rate of biocompatible Mg alloys make them unsuitable for implant applications. Reducing the corrosion rate of the alloys by altering the metallurgical properties can be potentially beneficial for such applications. Friction stir processing (FSP) is an established process to induce changes in the surface microstructure of metals, and in this study, this process has been explored as a potential method to modify the metallurgical microstructure of the alloy. There is an increase of 13 % of microhardness and there is a 21 % reduction in ultimate stress in exchange of 15 % increase in % elongation in friction stir processed AZ31 magnesium alloy. The results indicate that the induced changes in the metallurgical microstructure by FSP process can augment the resistance to corrosion without significantly deteriorating the mechanical properties as observed from tests conducted in a simulated biological environment. Further experimentation is required to optimize the processing condition and establish the relationship between the evolved metallurgical microstructures and the mechanical and electrochemical properties.