Constitutive equation for cyclic plasticity considering memorization of back stress

One of the difficult problems in the study of the constitutive equation for cyclic plasticity is the prediction of ratchetting behavior that is induced by the superposition of a cyclic secondary load to a constant primary load in a biaxial case, or by the mean stress in a uniaxial case. This paper shows the constitutive equation in which the memorization of the back stress is considered for ratchetting behavior, especially for biaxial ratchetting behavior. To verify the applicability of the constitutive equation to ratchetting behavior, a biaxial ratchetting test was carried out using SUS304 stainless steel at room temperature. As a result, it was found that the simulations based on the constitutive equation have good agreement with the tests. (author)