GB732440A - Improvements in or relating to sintered hard carbide products - Google Patents

Abstract

A metallic mass or article comprises Ti carbide and one or more carbides of Cr, Nb and/or Ta bonded by an austenitic steel containing Ni and/or Cr, the carbides constituting 20-90 per cent by weight of the product and the carbides and austenitic steel constituting at least 95 per cent of the product. The remainder may include impurities such as the carbides of Fe and Mn. Thus an example contains 61 parts of a mixture of 67.9 per cent of Ti carbide, 11.1 per cent of Cr carbide, 13.9 per cent of Nb carbide, 1.4 per cent of Ta carbide together with an austenitic steel containing 17 per cent Ni, 18 per cent Cr, 0.87 per cent Mn and 57.13 per cent of Fe-Ti (containing 35 per cent Ti) the balance being Fe and impurities. The mass or article may be produced by mixing the powdered carbides and the steel and either cold pressing and sintering or hot pressing in a protective atmosphere the heating in both cases being to a temperature of 1350-1900 DEG C. and being followed by quenching so that the structure of the steel is austenitic. Specification 669,588 is referred to. The Provisional Specification describes also masses or articles in whch carbides of one or more of Ti, Cr, Nb and Ta are used and refers to their production by a process of melting, casting and forging.