Effect of process parameters and VC content on structural and mechanical properties of WC-20Co nano composites

Abstract

The effect of process parameters and vanadium carbide on hardness, toughness and structural properties of the tungsten carbide-cobalt (WC-Co) nanocomposite has been investigated using micro-hardness tester, X-ray diffraction and scanning electron microscopy (SEM) with attached energy dispersive spectroscopy, respectively. To suppress grain growth, a high percentage (upto 10 wt. %) of vanadium carbide (VC) has been taken as a grain growth inhibitor as well as a hardener. WC-20Co composite with 7.5 wt% VC, heat treated at 1100 °C holding time for 2 hours, possesses high hardness (1687 HV) when the volume fraction of tungsten carbide (WC) and Co₆W₆C phases have been taken in the ratio of 2:1. High hardness and toughness have been obtained at 1100 °C for 2 h heat-treated sample. High VC content with 8 h holding time has increased the porosity in the samples.