Novel single crystalline-like non-equiatomic TiZrHfNbTaMo bio-high entropy alloy (BioHEA) developed by laser powder bed fusion
Ozkan Gokcekaya, Takuya Ishimoto, Yuki Nishikawa, Yong Seong Kim, Aira Matsugaki, Ryosuke Ozasa, Markus Weinmann, C. Schnitter, Melanie Stenzel, Hyoung Seop Kim, Yoshitsugu Miyabayashi, Takayoshi Nakano
Abstract
This study developed a non-equiatomic Ti28.33Zr28.33Hf28.33Nb6.74Ta6.74Mo1.55 super-solid solutionized BioHEA using laser powder bed fusion (LPBF) to reach the full potential as BioHEA. We succeeded in significant suppression of elemental segregation, thus, resulting in a single crystalline-like texture by activating layer-to-layer epitaxial growth. Relatively low Young’s modulus was achieved in the single crystalline-like BioHEA. Moreover, LPBF-fabricated BioHEA exhibited significantly higher yield stress (1355–1426 MPa) due to the effective solid solution hardening compared to as-cast counterpart with marked segregation (949 MPa), and good biocompatibility. This is first report achieving BioHEA with low modulus, excellent strength-ductility balance, and good biocompatibility via LPBF.