INFLUENCE OF VOID DISTRIBUTION ON YIELD SURFACES OF POROUS DUCTILE MATERIALS

Resumo

This work deals with numerical simulation of the mechanical behavior of materials composed
of heterogeneous ductile microstructures in presence of voids using a multi-scale approach considering
plasticity processes. This kind of material has been used in several applications as structural solutions.
Therefore, studies about yield surfaces of porous ductile materials are essentials to understanding its
mechanical behavior for safety reasons. The numerical modeling is performed in microstructures using
the concept of RVE (Representative Volume Element) considering the matrix as considered an ideally
plastic material governed by von Mises model with isotropic hardening. Different distributions of voids
are analyzed in order to investigate its influence on the proposed yield surfaces. In general way, the
RVEs containing concentrated void present yield surfaces with lower values when compared to the other
cases therefore the concentration of voids in the RVE decreases its mechanical strength. On the other
hand, the RVEs containing random distributions of voids present yield surfaces with high values and
RVEs containing symmetric distributions of voids present yield surfaces with intermediate values.