Hot deformation characteristics and kinetics analysis for Ni‐based corrosion resistant alloy

The hot deformation characteristics of Nickel‐based corrosion resistant alloy was studied in the temperature range of 1050°C to 1200°C and the strain rate range of 0.001 to 0.1 second −1 by employing hot compression tests. The results show that the peak stress increases with decreasing temperature and increasing strain rate, and the apparent activation energy is about 409 kJ/mol. Based on the Avrami equation through using the critical strain ( ε c ) and the strain for 50% DRX ( ε 0.5 ), a kinetic model for dynamic recrystallization (DRX) was established, where the model parameters could be obtained using the modified Zener‐Hollomon parameter ( Z *). Applying the model, the predicted value of the steady‐state strain ( ε ss ) and the strain for maximum softening rate ( ε m ) agree well with the experimental results. Accordingly, the relationship between ε m and ε 0.5 is established, which is mainly dependent on the Avrami exponent ( n ). When n  < 3.25, ε m becomes less than ε 0.5 and the difference in between decreases with increasing the strain rate or decreasing the deformation temperature. Finally, through observing DRX microstructure under different deformation conditions, a power law relation between DRX grain size ( D drx ) and Z *, with an exponent of −0.36, was found.