Characterization of fine-grained W-10 wt.% Cu composite fabricated by hot-shock consolidation

Abstract In this study the W-Cu composites have been fabricated by hot-shock consolidation and then their mechanical properties were estimated by nano-indentation experiments. The initial powders were preheated to 700-1000°C in less than 3 min, then consolidated under shock pressure within range of 3-4 GPa instantaneously. A W-Cu composite with the highest relative density of 96.3% was obtained without any sintering activator. The grain size of consolidated sample is nearly the same as its initial size of 2 μm. The samples were characterized using light microscopy (LM) and scanning electron microscopy (SEM). It was found that the homogeneous distribution of copper is the key factor for the consolidation of W-Cu powder, which is dominated by preheating temperature. High temperature improves the distribution of copper and enhances the bonding of W-Cu, but also leads to agglomerating of Cu while exceeding a specific value. The main mechanisms of the densification of W particles are void collapse and plastic deformation, which are dominated by the shock pressure.