Comparison of microstructure, crystallographic texture, and mechanical properties in Ti–15Mo–5Zr–3Al alloys fabricated via electron and laser beam powder bed fusion technologies

• DOI: 10.1016/j.addma.2021.102329
• Publication Date: 2021-09-28T01:56:52Z
• Authors: Shi-Hai Sun; Koji Hagihara; Takuya Ishimoto; Ryoya Suganuma; Yun-Fei Xue; Takayoshi Nakano
• Keywords: Texture (cosmology); Selective Laser Melting; Ductility (Earth science)

Depending on the application, establishing a strategy for selecting type of powder bed fusion technology—from electron beam (EB-PBF) or laser (L-PBF)—is important. In this study, we focused β-type Ti–15Mo–5Zr–3Al alloy (expected hard-tissue implant applications) as model material, and examined variations in microstructure, crystallographic texture, resultant mechanical properties specimens fabricated by L-PBF EB-PBF. Because melting mode transforms from conduction to keyhole with an increase energy density L-PBF, relative L-PBF-built specimen decreases at higher densities, unlike that EB-PBF-built specimen. Although both EB-PBF can obtain cubic textures via bidirectional scanning 90° rotation each layer, formation mechanisms were found be different. The <100> texture build direction is mainly derived vertically grown columnar cells EB-PBF, whereas it horizontally L-PBF. Consequently, different developed without layer: <110> aligned along respectively. exhibited considerably better ductility, but slightly lower strength than specimen, under conditions same density. We attributed variation microstructures specimens; α-phase was completely absent results demonstrate importance properly two technologies according material its application.