Development of TiNbTaZrMo bio-high entropy alloy (BioHEA) super-solid solution by selective laser melting, and its improved mechanical property and biocompatibility

Abstract BioHEAs, specifically designed high entropy alloy (HEA) systems for biomedical applications, represent a new era biometals. However, recent challenges are (1) the poor shape customizability, and (2) inevitable severe segregation due to intrinsic fact that HEA is an ultra-multicomponent system. To achieve customization suppression of elemental simultaneously, we used extremely cooling rate (~107 K/s) selective laser melting (SLM) process. We, first time, developed pre-alloyed Ti1.4Nb0.6Ta0.6Zr1.4Mo0.6 BioHEA powders SLM-built parts with low porosity, customizable shape, excellent yield stress, good biocompatibility. The specimens showed drastically suppressed compared cast counterpart, representing realization super-solid solution. As result, 0.2% proof stress reached 1690 ± 78 MPa, which significantly higher than (1140 MPa). promising as next-generation metallic material applications.