MECHANICAL PROPERTIES OF FINE-GRAINED STRUCTURES USING COMPUTATIONAL CELL ELEMENTS

摘要

Mechanical properties of fine-grained microstructure are predicted using a phase mixture model. The constitutive model is implemented into commercial finite element analysis code ABAQUS as a UMAT subroutine. A unified constitutive model based on dislocation density evolution describes the matrix phase behavior. The yield criterion of the Gurson-Tvergaard-Needleman material model for porous materials is applied to the boundary phase. The boundary phase is assumed to behave like a quasi-amorphous material. The effect of the grain size on the material property is studied using a numerical example.