Quantitative characterization of the microstructure and properties of nanocrystalline WC–Co bulk

Graphical abstract: Microstructure of the nanocrystalline WC–Co cermet bulk was quantitatively described by transmission electron microscopy based precession electron diffraction technology. It is discovered that the fraction of the Σ2 grain boundaries increases with the decrease of WC grain size. The effect of microstructure on mechanical properties depends on Co distribution, Σ2 boundaries fraction and WC grain contiguity. -- Nanocrystalline WC–Co bulk was prepared using a novel route that combined in situ reactions and subsequent spark plasma sintering. The microstructure was characterized by transmission electron microscopy-based precession electron diffraction technology. The nanocrystalline microstructure has a high WC grain contiguity. The fraction of Σ2 boundaries increases with a decrease in WC grain size. The effect of microstructure on the mechanical properties was analyzed in terms of the correlations between Co distribution, Σ2 boundary fraction and WC grain contiguity.