Cemented carbide

Abstract

A cemented carbide of the invention contains at least one of cobalt and nickel; calcium, sulfur, aluminum, silicon and phosphorus; balance tungsten carbide; and unavoidable impurities. The content of cobalt or nickel should range from 4 to 35% by weight. The content of each of calcium, sulfur, aluminum and silicon should be no greater than 50 ppm by weight, while the content of phosphorus should be no greater than 20 ppm by weight. The tungsten carbide has an average crystal grain size of 0.2 to 1.5 micrometers. The cemented carbide may further contain 0.1 to 40% by weight of at least one compound which may be carbides of metals in Groups IVa, Va and VIa of the Periodic Table other than tungsten, nitrides of metals in Groups IVa and Va of the Periodic Table and solid solution of at least two of the carbides and nitrides.

Dependencies are inferred from the claim text.