METHOD FOR PRODUCTION OF SINTERED HARD ALLOY Russian patent published in 1995 - IPC

FIELD: powder metallurgy; production of fine-grained and specially fine-grained sintered hard alloys based on tungsten carbide. SUBSTANCE: used during mixing of carbides of tungsten and cobalt by combined grinding is powder of tungsten carbide with average grain size of 1.2-4.5 μm, specific surface of 0.13-0.85 sq.m/g and grain size homogeneity characterized by median diameter d₈₀/d₂₀ amounting to 1.8-3.5. Grinding is continued to obtain specific surface of mixture of 2.6-3.8 sq.m/g. Subsequent molding and sintering result in production of alloys with average WC grain size of 1-1.5 μm, bending strength of 1600-1800 MPa and hardness of 92-92.5 HRA. EFFECT: higher efficiency. 1 tbl