Microstructure and mechanical properties of electron beam welded dissimilar TiAl/Ti60 joint

Electron beam welding experiments of TiAl/Ti60 dissimilar joints were carried out.Microstructure and mechanical properties were studied.The results show that major defect in TiAl/Ti60 joint during electron beam welding is transverse crack.Weld zone is characterized by acicular α₂ plates, HAZ near to Ti60 by acicular α' phase, and HAZ near to TiAl by martensite.Hardness in weld zone is relatively higher, as well as the hardness gradient along fusion line.Fracture during stretching occurs in the region near fusion line.Fracture mode is brittle fracture, which is characterized by transgranular fracture.