Electric-discharge compaction of graded WC–Co composites

Electric-discharge compaction (EDC) of nanocrystalline and coarse WC–Co powders to produce graded WC–Co cemented carbides was conducted in this work. Coarse and ultrafine graded WC–Co cemented carbides which offer high hardness and excellent fracture toughness was produced simply by EDC; the microstructure and mechanical properties of graded materials are also investigated. As a consequence of the short holding time in EDC, cobalt migration which always occurred in graded WC–Co during liquid phase sintering process due to the difference in WC grain sizes was kinetically constrained in the present study. It may offer a novel simple processing route to fabricate graded materials.