Grains of superabrasive material may be infiltrated with a molten metal alloy at a relatively low temperature, and the molten metal alloy may be solidified within interstitial spaces between the grains of superabrasive material to form a solid metal alloy having the grains of superabrasive material embedded therein. The solid metal alloy with the grains of superabrasive material embedded therein may be subjected to a high pressure and high temperature process to form a polycrystalline superabrasive material. A polycrystalline superabrasive material also may be formed by depositing material on surfaces of grains of superabrasive material in a chemical vapor infiltration process to form a porous body, which then may be subjected to a high pressure and high temperature process. Polycrystalline compacts and cutting elements including such compacts may be formed using such methods.

An abrasive particle having an irregular surface, wherein the surface roughness of the particle is less than about 0.95. A method for producing abrasive particles having a unique surface morphology including providing a plurality of abrasive particles; providing a plurality of metal particles; mixing the abrasive particles and the metal particles to form a mixture; compressing the mixture to form a compressed mixture; heating the compressed mixture; and recovering modified abrasive particles.

A method of forming a mixture including a ceramic material into a sheet, sectioning at least a portion of the sheet using a mechanical object and forming at least one shaped abrasive particle from the sheet, such that the at least one shaped abrasive particle can have a two-dimensional shape as viewed in a plane defined by a length and a width of the shaped abrasive particle selected from the group consisting of polygons, ellipsoids, numerals, Greek alphabet characters, Latin alphabet characters, Russian alphabet characters, complex shapes having a combination of polygonal shapes, and a combination thereof.

A grinding tool includes a substrate having a surface provided with a plurality of openings, and a plurality of grinding studs. Each of the grinding studs includes a stud portion and an abrasive particle attached to each other, the stud portions being respectively attached into the openings, and the abrasive particles protruding outward from the surface, each of the abrasive particles having a pattern cut across a tip thereof to define multiple apexes adjacent to one another. In some embodiments, methods of fabricating a grinding tool are also described.

A method of forming an abrasive article includes depositing a mixture into an opening of a substrate, contacting an exposed surface of the mixture in the opening to a texturing form to form a textured preform, and removing the mixture from the opening and forming an abrasive particle having a textured surface.

Embodiments of the invention relate to thermally-stable polycrystalline diamond compacts (PDCs), and methods of fabricating such PDCs. In an embodiment, a PDC includes a substrate and a pre-sintered polycrystalline diamond (PCD) table bonded to the substrate. The pre-sintered PCD table includes bonded diamond grains defining a plurality of interstitial regions. The pre-sintered PCD table further including a first region remote from the substrate including a nonmetallic catalyst and a metallic catalyst each of which is disposed interstitially between the bonded diamond grains thereof, and a second region bonded to the substrate including a metallic-catalyst infiltrant disposed interstitially between the bonded diamond grains thereof. A nonplanar boundary is located between the first region and the second region.

Sialon materials contain HFO.sub.2 in a maximum of 1 mass-% as a sintering additive, methods of producing them and methods of using them an /-SiAlON material with 5 mass % to 50 mass %, /(/) RE--SiAlON wherein RE stands for at least one cation selected from the group consisting of Y, Sc, Lu, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Mg or Ca, and 95 mass % to 50 mass %, /(/) -SiAlON and of an Hf-containing amorphous or partially crystalline grain-boundary phase with a proportion with respect to the overall material is below 10 vol %, wherein the Hf content of the sintered material is 0.2 mass % to 1.0 mass %, and of a dispersion phase comprising globular particles with a mean particle size of from 0.2 m to 15 m, containing at least one hard material selected from the group consisting of SiC, TiN, TiC, Ti(C,N), carbides of further elements of groups IVb, Vb and VIb of the periodic system, nitrides of further elements of groups IVb, VB and VIb of the periodic system, scandium carbide and scandium oxycarbide, which are contained in the sintered compact in a proportion from 5 vol % to 30 vol %.

A cubic nitride compact containing a polycrystalline mass of cubic boron nitride particles, present in an amount of at least 70 percent by volume, and a binder phase, which is metallic in character. In addition, a compact in which the binder phase is preferably superalloy in character.

A cubic nitride compact having a polycrystalline mass of cubic boron nitride particles, present in an amount of at least 70 percent by volume and a binder phase, which is metallic in character. In addition, a compact in which the binder phase is preferably superalloy in character.

The present invention provides dense silica particles with reduced metal impurities. Specifically, the present invention provides a colloidal silica produced by using an alkyl silicate as a starting material, wherein, with respect to a sample prepared by adding, as an internal standard, 1 wt. % of polydimethylsilane to a dried product of the colloidal silica, a peak area value calculated using a formula of a colloidal silica peak area/a polydimethylsilane peak area is 15 or less, the peak areas being determined by an obtained solid-state .sup.29Si-CP/MAS-NMR spectrum. The present invention further provides a method for producing the colloidal silica.