Elastoplastic Mesoscale Homogenization of Composite Materials

摘要

Mesoscale homogenization provides a computationally 'efficient way of capturing some degree of local variation in the behavior of a composite microstructure. In this work, techniques are explored in which the local two-phase microstructure is homogenized using the moving-window generalized method of cells (GMC) technique. Both elastic and plastic material behavior is investigated using GMC-generated anisotropic stress-strain curves. An optimization procedure is used to define Hill's yield criterion parameters which best fit the GMC-generated data. Two perfectly plastic models are developed based on the GMC results; these are called the subcell initial yield model and the matrix average yield model. A technique is also developed which, incorporates hardening behavior., Different windowing techniques are investigated: an overlapping windowing technique which requires more computational time, and a nonoverlapping tech-nique which requires less computational time. It is found-that the matrix average model using small nonoverlapping windows is the best technique in the cases studied, combining accuracy and computational efficiency.