W–Cu composites subjected to heavy hot deformation

Abstract

The effect of plastic deformation on the properties and microstructure of W–Cu composites produced by multi-pass hot extrusion with steel cup was investigated. W–Cu composites were sintered at 1 100 °C and then the sintered billets were firstly extruded at 900 °C with different extrusion ratios. The second hot extrusion was performed at 900 °C. The plastic deformation of copper phase plays a dominant part during the whole extrusion process. The microstructural evolution of W phase during the whole processing of heavy hot deformation can be divided into different stages. Experimental results indicate that the W agglomeration will be broken into fine particles effectively when the accumulated plastic deformation amounts to 97.6 % after the second extrusion.