Patent ID: 7179319
Filing Date: 2007-02-20
Classification: B22F,C22C,Y10T

Abstract:
1. A fine grained sintered cemented carbide containing chromium, comprising a first phase based on tungsten carbide which is bound by means of a second phase of a metallic binder based on Co or CoNiFe, and of at least one additional phase comprising at least one carbide or mixed carbide of tantalum, the sintered cemented carbide contains approximately 0.3 to 4% Ta, as related to the total mass of the sintered cemented carbide, the tungsten carbide has a grain size of between about 0.1 and about 1.3 μm, the binder phase contains the metals W, Cr and Ta, dissolved in solid solution, and the at least one additional phase comprises a TaC phase visible by optical microscopy.