Joining of γ-TiAl to low alloy steel by electron beam welding

Abstract

The weldability of cast γ-TiAl with a low alloy steel by electron beam welding was investigated in this study. It was found that when a higher heat input was employed, solid state cracking appeared in the welds due to a high thermal stress, as well as formation of a brittle TiC phase and a small fraction of Ti₃Al intermetallic. Crack free welding could be achieved if welding parameters were properly controlled such that thermal stress was released and formation of TiC and Ti₃Al was minimised.