Effect of welding speed on microstructural and mechanical properties of EB Ti-15V-3Al-3Cr-3Sn welds

Abstract

In the current study, the influence of welding speed (500, 700 and 800 mm/min) and post-weld heat treatment (PWHT) on microstructure and mechanical properties of electron beam welded Ti-15V-3Al-3Cr-3Sn was systematically studied. The welds at 800 mm/min welding speed showed higher ultimate tensile strength (UTS) (751 MPa), and hardness (245 HV) compared to welds prepared with 500 mm/min welding speed (UTS 670 MPa; hardness 235 HV). The higher strength at 800 mm/min welding can be attributed to the lower columnar width of β grains and the formation of equiaxed grains at the weld root and centre. A significant increase in UTS and hardness values was observed in samples subjected to the post-weld heat treatment (PWHT) for all the weld speeds.