AbstractÐThe accuracy of a hybrid continuum±micromechanical model for predicting the rate-dependent consolidation of metal powder was established using measurements from hot isostatic pressing (HIP) and hot triaxial compaction (HTC) experiments. The experiments were performed with PREP 1 Ti±6Al±4V powder encapsulated in thin-walled containers and yielded relative density vs time and height vs relative density data for direct comparisons with model predictions. The model was found to underpredict the den-si®cation rate in HIP, primarily during the early stages of consolidation, and the degree of consolidation during HTC. Adjustments to the values of the strain-rate sensitivity or a state variable representing the geometric structure of powder compacts resulted in good agreement between hybrid model predictions and measurements. The physical basis for discrepancies between predictions and measurements and justi®cation for the postulated/required parameter adjustments were attributed to two factors: (1) dierences in microstructure between the unconsolidated powder and the fully consolidated material used in the compression testing to obtain the material coecients for the model; and (2) interparticle bonding characteristics/particle sliding eects not taken into account in determining the material properties for the model.