Enhancing the hardness/compression/damping response of magnesium by reinforcing with biocompatible silica nanoparticulates

Low volume fraction silica nanoparticulate-containing magnesium composites targeting structural and biomedical applications were synthesized using the blend-press-sinter powder metallurgy technique followed by hot extrusion, and subsequently characterized for their microstructural, mechanical and damping properties. The results of microstructural characterization revealed a maximum similar to 32% reduction in grain size with 2 vol.% addition of SiO2 nanoparticulates. The compressive properties of pure magnesium increased with the addition of SiO2 nanoparticulates with Mg-2 vol.% SiO2 nanocomposite exhibiting the maximum 0.2% compressive yield strength and compressive fracture strain. The addition of SiO2 nanoparticulates enhanced the damping characteristics of pure magnesium with Mg-2 vol.% SiO2 nanocomposite exhibiting the maximum damping capacity and damping loss rate with a minimum change in elastic modulus which is favorable when targeting magnesium for biomedical applications. An attempt has also been made in this study to compare the biomechanical properties of synthesized Mg-SiO2 nanocomposites with those of natural bone.