cubic boron nitride sintered material including 90.0% by mass or more and 99.5% by mass or less of cubic boron nitride and 0.5% by mass or more and 10.0% by mass or less of silicon, wherein the cubic boron nitride sintered material has a total content of the cubic boron nitride and the silicon of 94.0% by mass or more and 100% by mass or less.

A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

A composite polycrystal contains polycrystalline diamond formed of diamond grains that are directly bonded mutually, and non-diamond carbon dispersed in the polycrystalline diamond, and has a concentration of contained hydrogen of less than or equal to 1000 ppm.

A composite polycrystal contains polycrystalline diamond formed of diamond grains that are directly bonded mutually, and non-diamond carbon dispersed in the polycrystalline diamond, and has a concentration of contained hydrogen of greater than 1000 ppm and less than or equal to 20000 ppm.

This application describes a method of making a super-hard article that includes a super-hard structure bonded to a substrate. The super-hard structure generally includes a sintered plurality of super-hard grains made from cubic boron nitride. The method generally includes providing raw material powder suitable for sintering the super-hard structure; combining the raw material powder with an organic binder material in a liquid medium to form a paste; providing a substrate assembly having a formation surface area configured for forming a boundary of the super-hard structure, the substrate having a recess coterminous with the formation surface area; extruding the paste into contact with the formation surface area to provide a paste assembly; and heat treating and/or sintering the paste assembly to remove the binder material and provide a pre-sinter assembly.

The disclosure describes techniques for infiltrating a porous preform with a slurry to form an infiltrated-preform, where the slurry includes a plurality of solid particles, where the plurality of solid particles include a plurality of fine ceramic particles defining an average fine particle diameter, a plurality of coarse ceramic particles defining an average coarse particle diameter, and a plurality of diamond particles, where the average fine particle diameter is less than the average coarse particle diameter, and infiltrating the infiltrated-preform with a molten metal infiltrant to form a ceramic matrix composite (CMC) article.

The disclosure describes techniques for infiltrating a CMC substrate with a first slurry to at least partially fill at least some inner spaces of the CMC substrate, where the first slurry comprises first solid particles, drying the first slurry to form an infiltrated CMC including the first solid particles, depositing a second slurry including a carrier material and second solid particles on a surface of the infiltrated CMC, where the second solid particles comprise a plurality of fine ceramic particles, a plurality of coarse ceramic particles, and a plurality of diamond particles, drying the second slurry to form an article having an outer surface layer comprising the second solid particles on the infiltrated CMC, and infiltrating the article with a molten infiltrant to form a composite article.

A method of making polycrystalline diamond material includes providing a fraction of diamond particles or grains and a sintering additive, the sintering additive comprising a carbon source of nano-sized particles or grains, forming the diamond particles and sintering additive into an aggregated mass, consolidating the aggregated mass and a binder material to form a green body, and subjecting the green body to conditions of pressure and temperature at which diamond is more thermodynamically stable than graphite and for a time sufficient to consume the sintering additive, sintering it and forming polycrystalline diamond material that is thermodynamically and crystallographically stable and is substantially devoid of any nano-structures.

Superabrasive compacts and methods of making superabrasive compacts are disclosed. A superabrasive compact includes a polycrystalline diamond table and a substrate attached to the polycrystalline diamond table. The substrate includes a hard metal carbide and a binder having a compound with a composition of A.sub.xB.sub.yC.sub.z, where A and B are transition metals, where C is carbon, and where 0≦x≦7, 0≦y≦7, x+y=7, and 0≦z≦3.

A high-pressure high-temperature, HPHT, diamond tool piece and a method of producing an HPHT diamond tool piece. At least a portion of the HPHT diamond tool piece comprises an aggregated nitrogen centre to C-nitrogen centre ratio of greater than 30%. The method includes irradiating an HPHT diamond material to introduce vacancies in the diamond crystal lattice, annealing the HPHT diamond material such that at least a portion of the HPHT diamond material comprises an aggregated nitrogen centre to C-nitrogen centre ratio of greater than 30%, and processing the HPHT diamond material to form an HPHT diamond tool piece.