Modeling the constitutive relationship of Cr_(20)Ni_2sMO_4Cu superaustenitic stainless steel during elevated temperature

摘要

Isothermal compression tests at temperatures of 1273-1473 K and strain rates ranging from 0.01 to 10 s~(-1) were preformed on Cr_(20)Ni_25Mo_4 Cu superaustenitic stainless steel to reveal the hot deformation characteristics. In order to give a precise prediction of flow behavior, the obtained experimental data was employed to derive the constitutive relationship incorporating the effect of strain. It is found that the effect of temperature and strain rate on flow stress is significant and their relationship can be represented by the Zener-Hollomon parameter including Arrheuins term. The material constant in the model, such as a, n, Qand In A functioned by the strain is identified using sixth order polynomial. The flow stresses calculated by the developed model are reasonable agreement with the experimental ones, which indicates that the constitutive relationship can effectively describe the high temperature flow behavior of Cr_(20)Ni_(25)Mo)4Cu superaustenitic stainless steel and can be used to numerically analyze the hot deformation process of the present material.