Microstructure and Fatigue Performance of Ti6Al4V Produced by Laser Powder Bed Fusion after Post-Heat Treatment

With the development of additive manufacturing (AM), Ti-6Al-4V alloy manufactured by laser powder bed fusion (LPBF) is becoming more widely studied. Fatigue fracture main failure mode such components. During LPBF processing, porosity defects are unavoidable, which hinders exploration relationship between fatigue performance and microstructure. In this study, a remelting method was used to reduce inside alloy. Three annealing treatments (AT) three solution-aging (SAT) were study effect two-phase zone (α + β) microstructure on life crack growth behavior. rate (CGR) curves obtained, surface analyzed. The results show that influences but has little CGR. Compared with as-built specimen, AT SAT specimens increased significantly at 850℃ 101 63.7 times, respectively. thickness α lath location nucleation together affect life. stable stage, layered colonies most resistant growth.