Effect of alloying elements and microstructure on the processing parameters of α2 aluminide alloys

The intrinsic workability of five Ti3Al base aluminide alloys was studied using power dissipation (PD) maps. The effects of aluminium, niobium and molybdenum on the workability were studied. In one of the alloys, the effect of starting microstructure on workability was also studied. While increase of Al beyond about 24 at% considerably reduced the workability, increase of Mo even beyond 1 at% embrittled the alloy. The workability went through a maximum at around 16-17 at% Nb. The MA structure consisting of equiaxed α2 exhibited better workability in comparison to cast structure consisting of widmanstatten α2. Through dynamic recrystallization (DRX) of α2 was readily observed in all the alloys, recrystallization of β/B2 could be achieved only statically.