A cubic boron nitride sintered material includes: more than or equal to 50 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 50 volume % of a binder phase, and when an oxygen content is measured in a direction perpendicular to an interface between cubic boron nitride grains using TEM-EDX, a first region having an oxygen content larger than an average value of an oxygen content of a cubic boron nitride grain exists, the interface exists in the first region, and a length of the first region along the direction perpendicular to the interface is more than or equal to 0.1 nm and less than or equal to 10 nm.

A polycrystalline super hard construction has a first region having a body of thermally stable polycrystalline super hard material having a plurality of intergrown grains of super hard material; a second region forming a substrate having a hard phase and a binder phase; and a third region interposed between the first and second regions. The third region includes a composite material having a first phase comprising a plurality of non-intergrown grains of super hard material, and a matrix material. A fourth region interposed between the second and third region has a major proportion having one or more components of the binder material of the second region, and one or more reaction products between the binder material of the second region and one or more components of the third region.

The present invention relates to the field of new materials technology, in particular to carbon nitride composite ceramic tool materials, preparation method and cutting tools thereof. The raw materials comprise carbon nitride, titanium carbonitride, molybdenum, nickel and cobalt, carbon nitride as the matrix phase, titanium carbonitride as the reinforcing phase are added to the carbon nitride based composite ceramic materials, with molybdenum, nickel and cobalt as a suitable sintering aid, dense composite tool material is obtained with vacuum hot press sintering method. The prepared carbon nitride based composite ceramic tool materials boast the advantages of low cost, high hardness, high bending strength and high fracture toughness, which is an important way to promote the innovation, development and popularization of carbon nitride materials.

A ceramic composite and a method of preparing the same are provided. The method of preparing the ceramic composite includes mixing an aluminum slag and a carbon accelerator to obtain a mixture and reacting the mixture at a temperature equal to or greater than 1600° C. in a nitrogen atmosphere to obtain a ceramic composite. The aluminum slag includes aluminum, oxygen, nitrogen, and magnesium. The weight ratio of the oxygen to the aluminum is 0.6 to 2. The weight ratio of the nitrogen to the aluminum is 0.1 to 1.2. The weight ratio of the magnesium to the aluminum is 0.04 to 0.2. The ceramic composite includes aluminum nitride accounting for at least 90 wt % of the ceramic composite.

The present invention is directed to a method for producing a silicon nitride sintered material, the method including heating a molded article, which contains a silicon nitride powder having a β phase ratio of 80% or more, a dissolved oxygen content of 0.2% by mass or less, and a specific surface area of 5 to 20 m.sup.2/g, and a sintering auxiliary containing a compound having no oxygen bond, and which has an overall oxygen content controlled to be 1 to 15% by mass and an aluminum element overall content controlled to be 800 ppm or less, to a temperature of 1,200 to 1,800° C. in an inert gas atmosphere under a pressure of 0 MPa.Math.G or more and less than 0.1 MPa.Math.G to sinter the silicon nitride.

In the present invention, there can be provided a method for producing a silicon nitride sintered material, which method is advantageous in that a silicon nitride sintered material having high thermal conductivity can be obtained even when using a silicon nitride powder having a high β phase ratio and conducting calcination under normal pressure or substantially normal pressure.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.

A polycrystalline super hard construction is disclosed having a first region comprising a body of thermally stable polycrystalline super hard material having an exposed surface forming a working surface, and a peripheral side edge, the polycrystalline super hard material comprising a plurality of grains of super hard material; a second region forming a substrate to the first region; and a third region interposed between the first and second regions. The third region extends across a surface of the second region along an interface, the interface comprising a portion having an uneven topology and a substantially planar portion, the third region comprising a composite material including a first phase comprising a plurality of non-intergrown diamond grains, and a matrix material.

This disclosure relates to polycrystalline cubic boron nitride material with cBN particles in a metal matrix comprising zirconium nitride and/or vanadium nitride precipitates or grains.

Provided is a boron nitride sintered body including boron nitride particles and pores, the boron nitride sintered body having a sheet shape and a thickness of less than 2 mm. Provided is a method for manufacturing a boron nitride sintered body, the method including a sintering step of molding and heating a blend containing a boron carbonitride powder and a sintering aid to obtain a sheet-shaped boron nitride sintered body including boron nitride particles and pores, in which a thickness of the boron nitride sintered body obtained in the sintering step is less than 2 mm.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 μm, intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.