LOW ORDER FINITE ELEMENT MODELING OF SIZE EFFECTS IN MICRO STRUCTURED MATERIALS BASED ON STRAIN GRADIENT PLASTICITY

摘要

A low order finite element method using theory of strain gradient plasticity along with Taylor dislocation model was developed to evaluate size effects occurring in micro structured materials. The gradient is evaluated in the framework of nonlinear incremental analysis where plastic strains are calculated and averaged at nodes then interpolated and differentiated. The proposed method was verified by solving typical size effect problems such as micro-bending, micro-indentation, and tensile test of a particle-reinforced metal matrix composite. The predicted results show clear length scale effect and close proximity to the respective experimental results.