Clustered void growth in ductile metals : final LDRD report.

This report is a compilation of projects completing during an investigation into void growth in ductile metals. Included, are the following results. (a) We have performed a suite of tests looking at the effect of porosity on the macroscopic yield stress of the material in a plane strain framework. Results have shown the orientation of voids to have a large effect on the yield stress. (b) Preliminary simulations of a periodic three dimensional void microstructure are given along with the meshing procedure. Results show less void interaction as compared to the two dimensional case. (c) Development and implementation of an anisotropic plasticity model is detailed. The model is used to replicate anisotropic necking seen in a tensile bar experimentally tested to failure. (d) We have shown efficiency gains of 84% of a 2D solution framework compared the standard 3D framework. (e) We investigated a large number of element formulations and have shown the q1p0 element (selectively integrated hex8) to outperform all others in the context of large deformation plasticity simulations. (f) The implementation of the q1p0 element into SIERRA is provided along with results of verification and performance investigations.