Densification mechanisms during hot isostatic pressing of stainless steel powder compacts

In order to analyse the densification behaviour of powder compacts during hot isostatic pressing (HIP) at elevated temperatures, a power-law creep constitutive model based on the plastic deformation theory for porous materials was applied to the densification. Various densification mechanisms including interparticle boundary diffusion, grain boundary diffusion and lattice diffusion mechanisms were incorporated in the constitutive model. The power-law creep model in conjunction with various diffusion models was applied to the HIP of 316L stainless steel powder compacts under 50 and 100 MPa at 1125 °C. The results of the calculations were verified using literature data. It could be found that the contribution of the diffusional mechanisms are not significant under the current process conditions.