Numerical and Experimental Analysis of Damage Evolution and Martensitic Transformation in AISI 304 Austenitic Stainless Steel at Cryogenic Temperature

In this research, ductile damage development and martensitic strain-induced phase transformation in plastic behavior of AISI 304 austenitic stainless steels at cryogenic temperatures are investigated. Nonlinear behavior of hardening and damage evolution could be observed in two-phase material as the result of strain-induced phase transformation. A simplified constitutive model for monotonic loadings, combining the effects of phase transformation and isotropic damage evolution has been introduced. Numerical analysis via implementing the model by means of a user subroutine UMAT in Abaqus/Standard is carried out. In addition, experiments including loading-unloading tensile test and X-ray diffraction test at cryogenic temperature 77K have been conducted to identify the parameters of the model and to compare with numerical results.