Constitution, Microstructure, and Hardness of Water Atomised and Hot Isostatically Consolidated Copper Alloy Powders

Abstract

Copper based alloys within the Cu–Cr–Zr system produced in powder form by water atomisation were consolidated to full density by hot isostatic pressing (hipping) at temperatures below 0·5T _m. After hipping, materials of a mean grain size between 2 and 10 μm were obtained. The increased capacity for solid solubility of chromium and zirconium in copper, produced on atomisation, resulted in enhanced strengthening by the precipitation of coherent chromium particles during hipping. This approach allowed heat treatment after processing as was the case for the extrusion-heat treatment route. The peak hardnesses obtained were either equal to (Cu–Cr–Zr alloys) or slightly lower than (Cu–Cr alloys) the respective values obtained after extrusion followed by heat treatment. PM/0618