INFLUENCE OF FLOW RULE AND INERTIA ON THE DUCTILE GROWTH OF VOIDS

As far as only volume changes are considered, the analysis of void growth during plastic straining of a material can be reduced to the two simple cases of (i) a cylindrical cavity submitted to axial and axisymmetric radial remote loads and (ii) a spherical cavity submitted to remote uniform mean stress. The latter are investigated for materials exhibiting either a power law or a linear stress-strain rate relationship. The influence of strain hardening is also considered in the case of spherical geometry. Finally, inertia effects are investigated. It is shown that both the linear strain rate dependence and inertia effects are likely to decrease void growth rate and thus to improve ductility at high strain rate.