Cold Isostatic Press

A cold isostatic press compacts a powdered material, commonly a metal, ceramic or hard carbide powder, into a solid shape by sealing it inside a flexible rubber or polymer mold and then applying uniform pressure from every direction through a surrounding liquid, without the high heat used in hot isostatic pressing. The technique developed alongside hot isostatic pressing in the mid-twentieth century as powder metallurgy and ceramic manufacturers sought a way to compact powders evenly into complex shapes before a separate sintering step fused the compacted powder into its final dense form. Because the surrounding liquid presses equally on every surface of the mold, cold isostatic pressing produces a more uniform density than pressing powder in a rigid single-direction die, and it remains a standard forming step for cutting-tool inserts, technical ceramics and other powder-based parts.