Synthesis of nickel-free bulk metallic glasses and their biomedical applications

A series of Ni-free Zr-based bulk metallic glasses have been developed. These Ni-free bulk metallic glasses show excellent mechanical properties, for instance 1.71 GPa tensile strength and 2.25% elasticity. Crystallization studies on these Ni-free alloys show a nano-sized icosaheral phase with a lattice constant of about 4.76 A followed by the formation of Zr 2Fe and other phases. The icosaheral phase possibly grows from a phase-separated region. The good mechanical properties of these alloys and the fact that they contain no Ni make them particularly interesting for biomedical applications. One of these would be to prepare stents from these Ni-free bulk metallic glasses to prevent aneurisms in the human brain.; Corrosion and cytotoxicity studies were performed on these Ni-free Zr-based alloys as well as on other Zr-based bulk metallic glasses. In simulated human body fluid, all Zr-based alloys have an extremely low free corrosion current, comparable to that of stainless steel 316L, while their breakdown potential is relatively low. Cytotoxicity tests on the Zr-based alloys also reveal their excellent viability and metabolic activity. Among the alloys, the Ni-free bulk metallic glass has the best metabolic activity, indicating that Ni as an alloying element negatively influences the biocompatibility of metallic glasses.