Method of making superhard articles

摘要

A superhard article is produced by heating in two steps a mixture of a hard-alloy matrix material and diamond grains less than 1 mm in size in a graphite press mould. During the first heating step, the mixture is heated to a temperature of 1,200 DEG C at a rate of 1,000 DEG -1,100 DEG C per minute by heating the press mould by high frequency. During the second heating step, the mixture is heated to the sintering temperature, up to 1,800 DEG C at a rate of 3,000 DEG -10,000 DEG C per minute by heating the mixture by the resistance method, i.e. by passing electric current through the mixture while simultaneously heating the press mould by high frequency currents.