Constitutive modelling for high temperature behavior of 1Cr12Ni3Mo2VNbN martensitic steel

The deformation behavior of 1Cr12Ni3Mo2VNbN martensitic steel in the temperature range of 1253 and 1453 K and the strain rate range of 0.01 and 10 s−1 are investigated by isothermal compression tests on a Gleeble 1500 thermal–mechanics simulator. Most of the stress–strain curves exhibit a single peak stress, after which the stress gradually decreases until a steady state stress occurs, indicating a typical dynamic recrystallization (DRX) behavior of the steel under the deformation conditions. The experimental data are employed to develop constitutive equations on the basis of the Arrhenius-type equation. In the constitutive equations, the effect of the strain on the deformation behavior is incorporated and the effects of the deformation temperature and strain rate are represented by the Zener–Holloman parameter. The flow stress predicted by the constitutive equations shows good agreement with the experimental stress, which validates the efficiency of the constitutive equations in describing the deformation behavior of the material.

► The hot compression tests were conducted in the temperature range of 1253–1453 K and the strain rate range of 0.01–10 s−1.
► The constitutive equations of 1Cr12Ni3Mo2VNbN martensitic steel considering the effect of strain were proposed.
► The developed constitutive equations can accurately reproduce the experimental flow stress and DRX behaviors.
► The constitutive equations were appropriate and reliable for the analysis of the hot deformation process of this material.