Impact performance and microstructures of thick TA1 titanium alloy sheets welded by vacuum electron beam

Thick TA1 titanium alloy sheets were thoroughly bonded by vacuum electron beam welding (EBW). The results indicated that microstructures in the weld zone (WZ) consisted of coarse α columnar grains, serrated α as well as needle-shaped α'; the microstructure in the heat-affected zone near the WZ side was composed of α' and α, while the microstructure near the base metal side consisted of α″ and α. The positional relation between the notches and rolling direction had an important role in the impact performance. The EBW joint exhibited higher absorbed impact energy at the weld seam after local heat treatment. Furthermore, lots of dimples were produced on the impact fracture surfaces, exhibiting ductile fractures.