A computational framework for low-cycle fatigue in polycrystalline materials

A three-dimensional framework for low-cycle fatigue analysis of polycrystalline aggregates is proposed in this work. First, a cohesive law coupling plasticity and damage developed modelling cycle-by-cycle degradation material interfaces up to complete de-cohesion failure. The may model both quasi-static under increasing monotonic load cyclic loading, through coupled plasticity-damage whose activation flow rules are formulated thermodynamically consistent framework. interface laws have been then implemented with multi-region boundary element formulation, the aim analysing intergranular aggregates. formulation allows expressing micro-mechanical problem terms grain-boundary displacements tractions only, which quantities directly entering laws, thus simplifying two tools. After assessing response an individual interface, loads, has employed computational investigation fully-3D pseudo-3D, or 2D columnar, aggregates, assuming that process remains confined regions. discussed results show potential multiscale materials modelling, find future application design engineering structures subjected complex loads processes, micromechanics, direct micro-electromechanical systems (MEMS).