All about Isostatic Pressing
Isostatic pressing is a powder metallurgy (PM) forming process that applies equal pressure in all directions on a powder compact thus achieving maximum uniformity of density and microstructure without the geometrical limitations of uniaxial pressing.
Isostatic pressing is performed “cold” or “hot.” Cold isostatic pressing (CIP) is used to compact green parts at ambient temperatures, while hot isostatic pressing (HIP) is used to fully consolidate parts at elevated temperatures by solid-state diffusion. HIP can also be used to eliminate residual porosity from a sintered PM part. Information from http://ipa-web.org/
Cold Isostastic Pressing (CIP)
Cold isostatic pressing has the advantage for producing parts where the high initial cost of pressing dies cannot be justified or when very large or complex compacts are needed. A variety of powders can be pressed isostatically on a commercial scale, including metals, ceramics, plastics, and composites. Pressures required for compacting range from less than 5,000 psi to more than 100,000 psi (34.5 to 690 MPa). Powders are compacted in elastomeric molds in either a wet or dry bag process.