Mechanical Fatigue Simulation by Unconventional Plasticity Model

The deformation behavior of a structure under cyclic loading condition is simulated by using FEM analysis in which a cyclic plasticity model, so-called extended subloading surface model, is incorporated. The adopted cyclic plasticity model is categorized in the framework of the unconventional plasticity model premising that the interior of the yield surface is not a purely elastic domain. The developed FEM program does not include algorithms for both the yielding-judgment and the control of stress so as to lie on the yield surface, since the subloading surface model has the stress controlling function so that a stress approaches the yield surface automatically. In this study, several examples of FEM analysis on the cyclic deformation behaviors are presented to show the potential of the developed FEM program and an incorporated cyclic plasticity model.