Effects of Powder Hardness and Particle Size on the Densification of Cold Isostatically Pressed Powders


Abstract: The densification behaviour of aluminium, iron and alumina powders under cold isostatic pressing (CIP) are examined. For this purpose, a unit which can withstand up to 650 MPa pressure was designed and constructed. With this pressure unit, aluminium, iron and ceramic powders, having different hardness values and different particle sizes, were pressed and their mechanical behaviours were investigated at pressures between 100 and 500 MPa. Attained densities were about 100% for aluminium, 90% for iron and 65% for alumina powders. Pressing resulted in significant increases in the microhardnesses of iron and aluminium powders. Light and scanning electron microscopy examinations revealed that severe plastic deformations took place in the powders of aluminium and iron, and no plastic deformation was observed in alumina powders.

Keywords: Cold Isostatic Pressing, Metallic and Ceramic Powders, Mechanical Behaviour.

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