High Entropy Zr-Ca-Si-Ti-Fe based Alloy for Biomaterial Application

Abstract

High Entropy Alloy (HEA) is relatively a new class material and have gained lots of interest to the researcher community in the recent years. They are characterized by unconventional compositions having multiple numbers of major alloying elements. HEA alloy contains at least five alloying elements with the concentration in a range of 5-35 at. % and minor elements <5 at.%. HEA multi-component alloys are often formed single solid-solution of single crystallographic phase; face centred cubic, body centred cubic or amorphous phase alloys. Their collective behaviour is mainly characterised by atomic size difference (δ), mixing enthalpy (ΔHmix) and mixing entropy (ΔSmix). They share many common properties with that of bulk metallic glasses (BMG). Therefore, highentropy bulk metallic glasses (HE-BMGs) provides an opportunity to study new type alloy system [1,2,3] In the present proposal development of Zr-Ca-Ti-Si-Fe based HE-BMG with a combination of biocompatible metals and modulus closer to that of bone had been attempted. However, it could be recalled that Phase diagrams for Zr-Ca, Ti-Ca are not available in ASM Metal Hand Books [8]. Therefore alloy development with Zr-Ca-Ti-Si-Fe composition is a challenging work