Contribution to anisotropic modeling of damaged ductile materials

A micro-mechanically motivated phenomenological model for the description o f the elastic-plastic behavior of anisotropic damaged metals containing ori ented microvoids at finite deformations is presented. The model is derived in the framework presented by Xiao, Bruhns and Meyers with the poverty of exact integrability. As the damage-measure the coeffici ents of a tensor-valued Fourier-series are used and interpreted for ellipso idal voids. From energetic considerations on an elementary material cell, t he qualitative dependence of the elastic constants on the aspect-ratios of the voids can be shown. The anisotropic effect of damage is taken into acco unt phenomenologically within the scope of an effective stress concept by m eans of an isotropic tensor-valued function for the elastic compliances.