Abstract: A sintered cubic boron nitride (cBN) compact for use in a tool is composed of between about 60 and 80 vol-% cBN having a volumetric mean particle size of between about 3 to 6 &mgr;m and between about 40 and 20 vol-% of a ceramic binder phase. The ceramic binder is composed of between about 20 and 60 vol-% of one or more of a carbide, nitride, or boride of a Group IVB or VIB metal, and between about 40 and 80 vol-% of one or more of carbides, nitrides, borides, or oxides of aluminum. The cBN compact additionally contains between about 3 and 15 wt-% tungsten. The cBN compacts are especially useful in machining iron and like chemically reactive parts, especially where such parts are powder metal parts.

Abstract: A sintered supported polycrystalline diamond compact (PCD) having improved abrasion resistance properties is manufactured by subjecting diamond crystals placed in adjacency with a metal carbide support containing a catalyst/sintering aid to high pressure/high temperature (HP/HT) processing. Said PCD compact comprises: a) a body of diamond crystals comprising a mixture of about 60 wt % to about 80 wt. % of coarse fraction having an average particle size ranging from about 30 to 60 &mgr;m and a fine fraction being about not substantially greater than about 20% of the average particle size of said coarse fraction; and b) a support body comprising about 12 wt. % or less of a catalyst/sintering.

Abstract: A sintered cubic boron nitride (cBN) compact for use in a tool is composed of between about 60 and 80 vol-% cBN having a volumetric mean particle size of between about 3 to 6 &mgr;m and between about 40 and 20 vol-% of a ceramic binder phase. The ceramic binder is composed of between about 20 and 60 vol-% of one or more of a carbide, nitride, or boride of a Group IVB or VIB metal, and between about 40 and 80 vol-% of one or more of carbides, nitrides, borides, or oxides of aluminum. The cBN compact additionally contains between about 3 and 15 wt-% tungsten. The cBN compacts are especially useful in machining iron and like chemically reactive parts, especially where such parts are powder metal parts.