Surface Morphologies and Mechanical Properties of Mg-Zn-Ca Amorphous Alloys under Chemistry-Mechanics Interactive Environments

Abstract

Mg-Zn-Ca amorphous alloys are considered as potential bone implants. A large number of works have focused on the alloys under free corrosion environment. However, the real service environment of bone implants is a kind of chemistry-mechanics interactive environment in which the materials not only suffer corrosion by body fluids but also bear applied force induced by body movement. In order to imitate the real service environment, surface morphologies and mechanical properties of Mg-Zn-Ca amorphous alloys were studied under different chemistry-mechanics interactive environments in this paper. It was found that cracks and Ca/Mg phosphates formed on the surface of amorphous alloys. The compressive strength of the alloys decreased seriously but could still reach an acceptable value to avoid material failure. Fan-shaped patterns found on all the samples implied that brittle fracture was the main fracture form. Moreover, vein-like patterns could still be found in some areas, showing a locally plastic deformation. This was the reason why the alloy could maintain a high compressive strength after severe and interactive treatments. The study could guide related works in the establishment of experimental environments in the future, which will facilitate a more accurate biomedical evaluation of bone implants.