US Patent 7220480 Cemented carbide and method of making the same

A cemented carbide including WC, a binder phase based on Co, Ni or Fe, and gamma phase, in which said gamma phase has an average grain size <1 μm. A method of making the cemented carbide is provided in which the powders forming gamma phase are added as mixed cubic carbides of one or more of Ti, Ta, Nb, Zr, Hf and V, and a ratio, fWC, between an amount of WC (in mol fraction of WC) and an equilibrium gamma phase WC content at a sintering temperature (in mol fraction WC) is given by fWC=xWC/xeWC, wherein fWC is 0.6 to 1.0.