Densification of Irregular Powders During Hot Isostatic Pressing

Abstract The densification of irregular powders during hot isostatic pressing was examined experimentally and compared to predicted densification rates using the HIP'ing model for monosized spheres proposed by Arzt, Ashby and Easterling (AAE model). Experimental densification rates for irregular powders of copper and yttria were found to be greater than those predicted by the AAE model. Empirical relationships were developed and incorporated into the AAE model to account for the shape of particles. These relationships incorporated the morphological characteristics into the description of effective pressure on the particle contacts. The modified HIP'ing model was then used to predict densification rates for irregular copper and yttria powders. The predicted rates are higher, thus reflecting the more rapid densification of the non-spherical-shaped particles.