Development of rare-earth oxide reinforced magnesium nanocomposites for orthopaedic applications: A mechanical/immersion/biocompatibility perspective.

Magnesium-Zinc based nanocomposites containing cerium oxide nanoparticles were developed in the present work. A systematic study on their microstructure, mechanical properties, in vitro degradation behaviour, and cytotoxicity are presented. It was found that the developed nanocomposites exhibited excellent strength and toughness that are superior to the commercially available magnesium alloys. From corrosion perspective, nanocomposites exhibited reduced pH increase compared to pure Mg with Mg-0.5Zn/0.5CeO showing the least corrosion rate. Moreover, the developed nanocomposites exhibited no cytotoxicity to MC3T3-E1 pre-osteoblast cells. Based on the above findings, the feasibility of Mg-Zn/CeO nanocomposites for use as orthopaedic implants is systematically discussed. This study provides an insight into the development of new high-performance Mg alloy-rare earth oxide (REO)-based nanocomposites with superior mechanical properties and corrosion resistance while effectively avoiding the possible standing toxic effect of RE elements.