Microstructure and properties of electron beam welded joint of Ti–22Al–25Nb/TC11

Dissimilar joining of Ti–22Al–25Nb alloy and an α+βα+β titanium alloy TC11 were carried out using electron beam welding technique. The microstructure, microhardness, and mechanical properties of the joint have been investigated. The results show that EBW can be used the joining of dissimilar TC11 alloy and Ti–22Al–25Nb alloy. The microstructure of the heat affected zone (HAZ) of TC11 alloy is martensite α′α′ phase, a large quantity of O/α2O/α2 particles precipitate in the weld and the microstructure of the HAZ of Ti–22Al–25Nb alloy is B2 phase. The room-temperature tensile strength of the joint is higher than that of the TC11 alloy base, and the impact toughness value of the joint is found to be about 42% of that of the TC11 alloy base.