Hardness and Densification Behaviour of Copper and Bronze Powders Compacted with Uniaxial Die and Cold Isostatic Pressing Processes

A. Eksi, Faculty of Engineering and Architecture, Çukurova University, Adana, Turkey, M. K. Kulekci, Faculty of Technical Education, Mersin University, Tarsus, Turkey In this study hardness and densification behaviour of copper and bronze powders under wet bag cold isostatic and uniaxial die pressing processes are examined. In uniaxial pressing the specimens were compacted up to a pressure of 800 MPa. Cold isostatic pressing (CIP) resulted in better densification for both of the studied powder materials. Attained densities were 94 % for copper and 82 % for bronze powders. In uniaxial die pressing greater pressurisation was needed to attain the same densification that obtained with CIP. The microhardness of both of the studied materials were measured before and after pressing processes. Higher pressure resulted in dislocation and strain hardening and increased hardness of powders.