Tailoring the crystallographic texture of biomedical metastable β-type Ti-alloy produced via laser powder bed fusion using temperature-field simulations

Recently, the use of laser powder bed fusion (LPBF) to create crystallographic textures, such as single-crystal-like and polycrystalline textures, has attracted attention. However, the relationship between the LPBF conditions and the resulting texture is unclear. This study investigates the effects of the LPBF conditions (laser power and scanning speed) on the texture by estimating the solidification behavior using temperature-field simulations. Strong or highly random crystallographic textures were obtained in the metastable β-type Ti-15Mo-5Zr-3Al alloy under different fabrication conditions via LPBF. Herein, we show for the first time that laser power and scanning speed negatively and positively affect the solidification rate R, respectively, and do not affect the thermal gradient G significantly. Thus, when the laser power decreases and scanning speed increases, the G/R ratio decreases and polycrystal formation is enhanced. This is consistent with practical observations.