Investigation on Hot Deformation Behavior of Nitronic60 Austenite Stainless Steel

The hot deformation behavior of Nitronic60 austenite stainless steel was studied by high temperature isothermal compression test of cylindrical specimens at 950—1 200 ℃ with the strain rate of 0.01—10 s^-1 and true strain of 0.9 on a Gleeble-3800 simulated machine.The microstructure after hot deformation were analyzed.The results show that during the hot compression process the flow stress decrease with the increase of deformation temperature and decrease of strain rate.When the strain rate is low, the dynamic recrystallization of the steel occurs in the range of deformation temperature.The hot deformation constitutive relationship was established using the hyperbolic-sine mathematics model.Its activation energy is 425.542 kJ/mol, and the Zenner-Hollomon (Z) parameter and flow stress equation for compress deformation at high temperature is Z = εexp (425.542 /RT) = 3.495 × 10¹⁵[sinh (0.005 93σ) ]^5.55, ε= 3.495 × 10¹⁵[sinh (0.005 93σ) ]^5.55exp[- 525.524/(RT) ], respectively.