METHOD OF ACHIEVING COMBINATION OF HIGH HARDNESS AND CRACK RESISTANCE OF HIGH-DENSITY NANOSTRUCTURED TUNGSTEN CARBIDE ARTICLES Russian patent published in 2015 - IPC C04B35/56 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: invention relates to techniques of producing high-density articles by sintering workpieces made of packed nanodispersed tungsten carbide powder by spark plasma sintering (SPS) and can be used in making metal-working tools, targets for sputtering wear-resistant coatings of extremely loaded critical parts of machines, e.g. crankshafts of heavy armoured vehicles, as well as special-purpose materials with dynamic overstrength effect. Initial tungsten carbide powder with particle size of not more than 110 nm with volume ratio of WC of not less than 99% is sintered in pressing conditions thereof in a vacuum with an optimum rate selected in the range of 25-2400°C/min at temperature which is selected as a function of the particle size of the initial WC powder. When the rate of heating in said range increases, the hardness of the sintered workpiece increases, and when the rate decreases, the crack-resistance of the workpiece increases. Sintering temperature can be 1550-1800°C.

EFFECT: obtaining in said silicon carbide articles a highly dense uniform nanostructure with a difficult trade-off between high hardness and crack resistance.

4 cl, 5 ex, 2 dwg