PARAMETRIC STUDIES OF THE HOT ISOSTATIC PRESSING OF RAPIDLY SOLIDIFIED 304 STAINLESS-STEEL POWDER

The increasing importance of powder materials fabrication by use of hot isostatic pressing (HIP) has led to recent emphasis on analytical techniques for describing and understanding the process. Understanding of particle consolidation during the HIP process has been attempted through the modelling of densification behavior by considering the deformation of a representative particle due to forces transmitted through the particle contacts. However, the properties of HIPed material have not been thoroughly investigated in terms of their deformation maps and HIP parameters. Mechanical properties of a compact can be quite different depending on the location of various deformation map boundaries. Diffusional creep is involved not only in densification but also in bonding at particle contacts. HIP pressure increases mechanical contact and enhances density but not particle bonding per se. Discrepancies between experimental and calculated data points for shorter HIP times may have been affected by oxide film layer on the original powder.