An ABAQUS-Compatible User Subroutine UMAT Based On Two-Surface Constitutive Model For Cyclic Plasticity of Nonlinear Hardening Stainless Steels

摘要

Experimental test observations indicate that some austenitic stainless steels like Type 304 behave with nonlinear hardening phenomenon when subjected to nonproportional cyclic loading and unloading. To describe the cyclic plasticity of such materials, significant differences will be generated if using either pure isotropic rules or pure kinematic hardening rules that are available with general purpose finite element codes. Specific nonlinear hardening constitutive models must be developed and implemented with the finite element codes. This paper presents an ABAQUS user subroutine UMAT that is developed using the classic two-surface constitutive model to address such cyclic nonlinear hardening phenomenon. Comparisons with experimental test results of A23-304 stainless steel at 550 °F (288 °C) are made that show good accuracy when using the subroutine to handle one-dimensional and three-dimensional tension-compression problems.