The impact of graphene on the mechanical properties, corrosion behavior, and biocompatibility of an Mg–Ca alloy

This investigation explores the impact of incorporating graphene (Gr) reinforcement on the microstructure, mechanical properties, corrosion behavior, and biocompatibility of a composite derived from a magnesium–calcium (Mg–Ca) alloy. Two concentrations of Gr (0.1% and 0.2%) were introduced to an Mg–Ca alloy. The addition of 0.1% Gr resulted in a refined grain structure, enhancing both tensile and compression strength. However, electrochemical analysis and immersion testing revealed an increase in corrosion rate ($R_w$) with the incorporation of Gr. Although the corrosion rate of the Mg–Ca-0.1%Gr composite was comparable to that of Mg–Ca, the Mg–Ca–0.2%Gr exhibited higher corrosion rates attributed to the enhancement of micro-galvanic corrosion. Interestingly, cell survival rate tests demonstrated improved biocompatibility for the Mg–Ca–0.1%Gr sample, emphasizing its potential for applications in the biomedical domain, which requires enhanced mechanical strength, corrosion resistance, and biocompatibility.