Sintered polycrystalline cubic boron nitride body
AssigneeElement Six (UK) Limited
InventorsSantonu Ghosh, Martin Ryan Gardener
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Abstract
A sintered polycrystalline body and a method of forming the sintered polycrystalline body are disclosed. The sintered polycrystalline body comprises a plurality of particles cubic boron nitride dispersed in a matrix. The matrix includes materials selected from compounds of any of titanium and aluminium. The polycrystalline body further comprises 0.1 to 5.0 volume % of lubricating chalcogenide particles dispersed in the matrix. The chalcogenide particles have a coefficient of friction of less than 0.1 with respect to a workpiece material. Preferably sulfide particles are used as lubricant. Preferably 30-70 vol.-% cBN is contained. Sintering takes place at 1100-1600° C. and 4-8 GPa.
Claims10
A sintered polycrystalline body comprising:
- a plurality of particles of cubic boron nitride dispersed in a matrix, the matrix comprising materials selected from the group consisting of titanium carbonitride, titanium carbide, titanium nitride, titanium diboride, aluminum nitride and aluminum oxide;
- wherein the polycrystalline body comprises 0.1 to 5.0 volume % of lubricating chalcogenide particles dispersed in the matrix, the chalcogenide particles selected from the group consisting of tungsten disulphide, tantalum disulphide and molybdenum disulphide,
- wherein the sintered polycrystalline body further comprises titanium carbosulfide (TiCS2), and
- wherein the chalcogenide particles have a coefficient of friction of less than 0.1 with respect to a ferrous material.
A method of making a sintered polycrystalline body comprising:
- mixing a plurality of particles of cubic boron nitride with a matrix precursor material, the matrix precursor material comprising compounds for forming a compound selected from the group consisting of titanium carbonitride, titanium carbide, titanium nitride, titanium diboride, aluminum nitride and aluminum oxide;
- the sintered polycrystalline body further comprising titanium carbosulfide (TiCS2);
- the matrix precursor material further comprising chalcogenide particles, the chalcogenide particles selected from the group consisting of tungsten disulphide, tantalum disulphide and molybdenum disulphide, and having a coefficient of friction of less than 0.1 with respect to a ferrous material, wherein the chalcogenide particles from 0.1 to 5.0 volume % of the combined superhard material particles and the matrix precursor material particles;
- consolidating and sintering the plurality of particles of cubic boron nitride and the particles of matrix precursor material at a pressure of between 4 GPa and 8 GPa and a temperature of between 1100° and 1600° C.
Dependencies are inferred from the claim text.