Uniaxial and Biaxial Ratcheting of ST52 Steel under Variable Amplitude Loading – Experiments and Modeling

The paper shows results of experiments focused on the influence of loading frequency on ratcheting as well as interesting results obtained from uniaxial tests and biaxial tests with rectangular and circular loading paths under variable amplitude loading realized on the ST 52 steel at the VŠB-Technical University of Ostrava. The model based on the AbdelKarim-Ohno kinematic hardening rule and Calloch isotropic hardening rule was used for stress-strain behavior description in finite element analysis using commercial software Ansys. The material model was implemented into the FE code using a fortran subroutine. Results of simulations containing ratcheting and cyclic hardening effects correspond with experiments very well.