Preparation of V-element-containing Co-based composite powders by spray conversion and its effect on the microstructure properties of cemented carbides

Abstract

This study synthesized cobalt powder containing vanadium (V) through a spray transformation process combined with calcination and reduction. WC-6Co cemented carbide was subsequently produced using spark plasma sintering (SPS). This research examined the distribution of vanadium within the cobalt-based composite powder, and WC-Co cemented carbide and its effects on the materials' microstructure and properties. It was found that pre-introducing vanadium suppressed the Co phase transition from fcc to hcp during reduction, resulting in an expanded Co lattice constant. Additionally, the formation of (W, V)C_X carbides during sintering refined the WC grains, enhancing the comprehensive performance of the cemented carbide. Optimal Vickers hardness and wear resistance were achieved at a vanadium content of 1.0 wt.%, although there was a slight reduction in fracture toughness.