High-temperature compression deformation of the Ni3Al-based alloy with high Al content was investigated by thermal simulation using a strain rate of 0.01 to 1/s at 1200 to 1240C. A thermal deformation constitutive equation was established for the alloy. The results revealed that the thermal deformation constitutive equation was σ = 28.57(lnε̇+6.72x105/RT-44.08) when the strain rate was 0.01/s, while the thermal deformation constitutive equation was σ = 28.57(lnε̇+1.28x106/RT-92.76) when the strain rate was 0.1 and 1/s. There was only the γ′ phase re-dissolving to varying degrees, but without dynamic recrystallization occurring. The optimal deformation parameters for the alloy were a temperature of 1200 to 1215C and a strain rate of 0.01/s. When the strain rate increased to 1/s, due to the locked dislocation in the γ′ phase not being released, the β/γ′ interface was liable to crack through single γ′ phase, and the deformation condition corresponded to a so-called destabilization area.

Hot Deformation Behaviour of Ni3Al-Based Alloy with High Al Content. Zhang, X.E., Fu, S.S., Luo, H.L., Han, S.L., Li, S.P.: Journal of Aeronautical Materials, 2013, 33[1], 14-20