Cubic boron nitride/sintered carbide abrasive bodies

Claim 2

The combination of claim 1 wherein the mass of cubic boron nitride crystals is present as a layer having a thickness of about 0.060 inch or less.

Claim 3

A composite abrasive body comprising a mixture of metal bonded carbide and cubic boron nitride crystals, the metal bonded carbide being present in less than about 30 volume percent.

Claim 4

The abrasive body of claim 4 wherein the mixture contains diamond grains.

Claim 5

The process for preparing a composite abrasive body comprising the steps of: a. placing within an enclosure of protective metal a quantity of carbide powder containing metal bonding material therefor and a quantity of cubic boron nitride crystals, said quantity of carbide powder being predominately of carbide material selected from the group consisting of tungsten carbide, titanium carbide, tantalum carbide and mixtures thereof with the metal bonding material therein being selected from the group consisting of cobalt, nickel, iron and mixtures thereof, b. simultaneously heating said enclosure and the contents thereof to temperatures in the range of 1,300*-1,600*C and applying pressures thereto in excess of about 40 kilobars for at least 3 minutes, c. ceasing the input of heat to said enclosure, d. removing the pressure applied to said enclosure and e. recovering the composite abrasive body produced.

Claim 6

The process of claim 6 wherein the carbide powder and cubic boron nitride crystals are two contiguous discrete masses.

Claim 7

The process of claim 7 wherein the cubic boron nitride crystals are disposed in a layer over at least one flat surface of the mass of carbide powder, said layer being about 0.060 inch or less in thickness.

Claim 8

The process of claim 6 wherein the carbide powder and cubic boron nitride crystals are mixed together, the carbide powder being present in less than about 30 volume percent.

Claim 9

The process of claim 6 wherein the carbide powder contains tungsten carbide powder and cobalt powder.

Claim 10

The process for preparing a composite abrasive body comprising the steps of: a. placing within an enclosure of protective metal a metal bonded carbide body and contiguous therewith a smaller mass of cubic boron nitride crystals, said metal bonded carbide body being predominately of carbide material selected from the group consisting of tungsten carbide, titanium carbide, tantalum carbide and mixtures thereof with the metal bonding material therein being selected from the group consisting of cobalt, nickel, iron and mixtures thereof, said mass of cubic boron nitride crystals containing greateR than about 70 volume percent of cubic boron nitride crystals, b. simultaneously heating said enclosure and the contents thereof to temperatures in the range of 1,300*-1,600*C and applying pressures thereto in excess of about 40 kilobars for at least 3 minutes, c. ceasing the input of heat to said enclosure, d. removing the pressure applied to said enclosure and e. recovering the composite abrasive body produced.

Claim 11

The process of claim 11 wherein the cubic boron nitride crystals are disposed in a layer over at least one surface of the metal bonded carbide body, said layer being about 0.060 inch or less in thickness.

Claim 12

The process of claim 11 wherein the metal bonded carbide body contains tungsten carbide and cobalt.

Claim 13

The combination of claim 1 wherein the individual cubic boron nitride crystals are larger than about 80 micrometers in largest dimension.

Claim 14

The process of claim 6 wherein diamond crystals are also placed with the protective metal enclosure; the carbide powder, cubic boron nitride crystals and diamond crystals being mixed together, the carbide powder being present in less than about 30 volume percent.