Development of TiNbTaZrMo bio-high entropy alloy (BioHEA) super-solid solution by selective laser melting, and its improved mechanical property and biocompatibility. (15th March 2021)

• Record Type: Journal Article
• Authors: Ishimoto, Takuya; Ozasa, Ryosuke; Nakano, Kana; Weinmann, Markus; Schnitter, Christoph; Stenzel, Melanie; Matsugaki, Aira; Nagase, Takeshi; Matsuzaka, Tadaaki; Todai, Mitsuharu; Kim, Hyoung Seop; Nakano, Takayoshi
• Is Part Of: Scripta materialia. Number 194(2021)
• Publication Date: 2021-03-15
• Subjects: Selective laser melting -- High entropy alloy -- BioHEA -- Cooling rate -- Segregation suppression; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2020.113658
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: BioHEAs, specifically designed high entropy alloy (HEA) systems for biomedical applications, represent a new era for biometals. However, recent challenges are (1) the poor shape customizability, and (2) the inevitable severe segregation due to the intrinsic fact that HEA is an ultra-multicomponent alloy system. To achieve shape customization and suppression of elemental segregation simultaneously, we used an extremely high cooling rate (~10 7 K/s) of the selective laser melting (SLM) process. We, for the first time, developed pre-alloyed Ti1.4 Nb0.6 Ta0.6 Zr1.4 Mo0.6 BioHEA powders and SLM-built parts with low porosity, customizable shape, excellent yield stress, and good biocompatibility. The SLM-built specimens showed drastically suppressed elemental segregation compared to the cast counterpart, representing realization of a super-solid solution. As a result, the 0.2% proof stress reached 1690 ± 78 MPa, which is significantly higher than that of cast Ti1.4 Nb0.6 Ta0.6 Zr1.4 Mo0.6 (1140 MPa). The SLM-built Ti1.4 Nb0.6 Ta0.6 Zr1.4 Mo0.6 BioHEA is promising as a next-generation metallic material for biomedical applications. Graphical abstract: Image, graphical abstract