This research deals with the development of constitutive equations and computational procedures for improving the scientific basis for the analysis of hot deformation processing of metals, with special attention focused on predicting material processing defects which arise because of high porosity and deformation localization. The results from this research will be useful for the analysis of deformation and progressive damage of dense materials, and also for the analysis of hot deformation processing (e.g., hot isostatic processing - HIP'ing) of porous metals produced by compaction and sintering of metal powders.