Vacuum sintering of WC-8Â wt.% Co hardmetals from WC powders with different dispersity

► Vacuum sintering of WC-Co hardmetals produced from nanocrystalline WC powders is accompanied by their partial decarbonizing. ► The loss of carbon is observed already at minimum sintering temperature 800 °C and leads to an appearance of ternary carbide phases in hardmetals. ► Large density and uniform homogeneous microstructure are reached in nanostructured hardmetals at smaller sintering temperature than these in the hardmetals produced from coarse-grained WC powder. ► Use of nanocrystalline WC powder allows decreasing of the optimal sintering temperature of the WC-Co hardmetals by about 100 °C.