Multiple grade cemented carbide articles and a method of making the same

A multigrade cemented carbide article produced by the method comprising the steps of:

• a. partitioning a die into at least a first portion and a second portion, using a removable partition means;
• b. filling the first portion of the die with a first metallurgical powder, the first metallurgical powder comprising a blend of a carbide compound of an element selected from the group consisting of group IVB, group VB and group VIB elements and a binder comprising a metal selected from the group consisting of Co, Ni and Fe;
• c. filling the second portion of the die with a second metallurgical powder, the second metallurgical powder comprising a blend of a carbide compound of an element selected from the group consisting of group IVB, group VB and group VIB elements and a binder comprising a metal selected from the group consisting of Co, Ni and Fe;
• selecting the second metallurgical powder to be of a different grade from the first metallurgical powder in that at least one of a composition of the second metallurgical powder and a grain size of the second metallurgical powder is different from the first metallurgical powder;
• d. removing the partition means so that the first metallurgical powder and the second metallurgical powder come into contact with each other;
• e. compressing the first metallurgical powder and the second metallurgical powder as a single compact to a desired shape;
• and
• f. sintering the resultant single compacted shape at an appropriate temperature to produce a multigrade, composite cemented carbide article, the multigrade, composite cemented carbide article comprising a first cemented carbide portion, corresponding to the first portion of the die, and a second cemented carbide portion of a different grade from the first cemented carbide portion, and corresponding to the second portion of the die.