Tailoring properties of cast Mg10Gd by alloying Nd and heat treatment

Abstract

Magnesium-rare Earth alloys receive growing interest for medical applications as implant material due to their non-toxicity, high specific strength with moderate corrosion rate and elastic modulus comparable with bone. In this study, the corrosion properties of cast Mg10Gd modified with neodymium have been investigated by potentiodynamic measurements. Adding neodymium to Mg10Gd improves mechanical properties, but the influence on the corrosion behavior was rarely investigated. The heat treatment of Mg10Gd1Nd and Mg10Gd2Nd, especially T6, increased strength due to precipitation of prismatic plate precipitates. In most magnesium alloys, the degradation of α-Mg matrix preferentially due to the cathodic response of precipitates, the influence of type and distribution of the precipitates on the nature and dynamics of the corrosion process is discussed. The temperature increase from room to body temperature accelerates the corrosion processes. However, an extended repassivation is observed at higher temperatures.