High Thermal Stability of a Colony and Basket-Weave Mixed Microstructure in Selective-Laser-Melted Ti-6Al-4V AlloyInduced by Electropulsing

A colony and basket-weave mixed microstructure in the selective-laser-melted (SLM) Ti-6Al-4V alloy was introduced by electropulsing, which showed high thermal stability. The mechanism was investigated by electron backscatter diffraction (EBSD) and X-ray diffraction (XRD) analysis. It was found that the low content of the β-phase favored the inhibition of microstructure coarsening. The increasing β-phases during the stabilization annealing (700 °C/16 h) rendered the growth of α-lath and -colony. Moreover, the stabilization-annealed colony and basket-weave mixed microstructure still kept the high strength–ductility synergy.