Investigations on the correlation between microstructure evolution and properties improvement of wire arc additive manufactured intermetallic alloys

Titanium aluminide (TiAl) and nickel-titanium (NiTi) intermetallic alloys have attracted widespread attention owing to their outstanding properties, which are widely applied in aerospace and automobile engineering areas. Whereas, the weak points of poor ambient temperature plasticity and formability made TiAl alloys difficult to be machined into complex components, narrowing their practical application. Besides, it is also a hard task to fabricate NiTi parts because of the high reactivity and high ductility of the alloy which results in difficulties in the processing and machining, which altogether limited the starting form of NiTi devices to simple geometries. In recent years, additive manufacturing exhibits its potential to be a viable production route to fabricate TiAl and NiTi intermetallic alloys.