Cemented carbides with uniform microstructure

WC-Co cemented carbides with uni-modal grain size distribution were produce d using a very uniform WC powder. The uniform microstructures obtained in t his way do not contain any coarse carbide grains due to the absence of ultr a-fine grain fractions in the WC powder employed. Hence, the growth of WC g rains during liquid-phase sintering is suppressed and a narrow grain size d istribution can be achieved. Additions of TaC further improve the structura l uniformity of the cemented carbides developed. The physical and mechanica l properties of the WC-Co and WC-TaC-Co cemented carbides with the uniform structure are found to be up to 30% higher compared with the properties of conventional ones of the same composition, only as a result of their very h igh structural uniformity. The performance of such cemented carbides in met al-cutting is found to be noticeably improved compared with the performance of conventional cemented carbides.