Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phase, such as AlxByOz, for example.

Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phrase, such as AlxByOz, for example.

Abstract: A method of producing a PCD body includes the step of providing a region of coarser diamond particles between a source of binder phase and a region of fine grained diamond particles having a particle size less than 2 ?m. The binder phase is caused to infiltrate the diamond mass through the region of coarser diamond particles under elevated temperature and pressure conditions suitable to produce PCD.

Abstract: A process forming boron coated abrasives, in particular boron coated abrasive particles, which may be used in saw blade segments, grinding wheels and other grit-containing tools. While the process is particularly suited to the coating of abrasive particles, it can be applied to any abrasives for use in grinding, cutting or polishing tools, or to such tools themselves. In the case of abrasive particles, these are mixed with boron and boric acid powder, in a suitable ratio, and furnaced at a temperature between 800 and 1200° C. for a length of time in an inert atmosphere sufficient to coat the particles.

Abstract: An abrasive compact comprises an ultrahard polycrystalline composite material comprised of ultrahard abrasive particles having a multimodal size distribution and a binder phase. The ultrahard polycrystalline composite material defines a plurality of interstices, the binder phase being distributed in the interstices to form greater than an optimal threshold of binder pools per square micron.

Abstract: Polycrystalline diamond abrasive elements made by incorporating low levels of at least one metal boride, the metal being selected from magnesium, calcium, aluminium, strontium, yttrium, zirconium, hafnium and chromium, and the rare earth metals, particularly cerium and lanthanum. The benefits of adding boron to polycrystalline diamond abrasive compacts are exploited together with simultaneously minimising or eliminating the detrimental effects of the presence of oxygen.

Abstract: The present invention concerns a method of producing an ultrahard abrasive composite material having a desirable overall thermal expansion coefficient mismatch, between the ultrahard particles and their matrix materials. The method includes the steps of providing a volume fraction of ultrahard particles having a pre-determined thermal expansion coefficient; determining the volume fraction and thermal expansion coefficient of a matrix material that would be required to produce an ultrahard composite material having a desired overall thermal expansion coefficient mismatch; contacting the ultrahard particles and the matrix material to form a reaction volume; and consolidating and sintering the reaction volume at a pressure and a temperature at which the ultrahard particles are crystallographically or thermodynamically stable.

Abstract: The present invention concerns an ultrahard composite material comprising ultrahard particles dispersed in a nano-grain sized matrix material, wherein the average grain size of the matrix material, or at least one component of the matrix material, is within 30 nm of the Hall-Petch departure grain size for the matrix material or at least one component thereof. The ultrahard particles in the composite are cubic boron nitride and/or diamond, and the matrix materials are of a controlled and chosen phase and nano-grain size. Ultrahard composites with cubic boron nitride and diamond in nano-matrices of titanium nitride, zirconia, alumina, silica and chromium nitride are provided.

Abstract: Abrasive compacts, in particular ultrahard polycrystalline abrasive compacts, are made under high pressure/high temperature conditions and are characterized in that they include a coarser grained fraction of ultrahard particles distributed non-percolatively throughout a finer grained fraction of ultrahard particles, which may be regarded as a finer grained ultrahard particle matrix, in such a way that the individual coarser grains are largely isolated from one another. It therefore performs as a matrix of highly wear resistant finer grained material interspersed with larger grains, offering a structure that has advantageous wear and impact performance over the behaviours of the two components individually or otherwise combined.

Abstract: A diamond electrode comprises a polycrystalline mass of diamond particles bonded together and has a porous surface, or an at least partly porous surface. The porous surface of the electrode is typically created by leaching non-diamond material, such as a second phase of a metallic material, at least in part, from the bonded polycrystalline mass of diamond particles, either before or after shaping it into an electrode. Alternatively, or additionally, the porous surface of the electrode may be created by subjecting a mass of diamond particles to conditions of elevated temperature and pressure to self-bond the particles together in the absence of a second phase.

Abstract: A composite material comprises a plurality of cores of material selected from the group comprising carbides, nitrides, carbonitrides, cemented carbides, cemented nitrides, cemented carbonitrides and mixtures thereof, dispersed in a matrix. The matrix comprises the components for making an ultra-hard material, such as diamond or cBN abrasive particles, and a suitable binder. The ultra-hard material is polycrystalline in nature and is typically PCD or PcBN. The cores are typically provided as individual particles or in the form of granules. The granules may be further coated with a second coating, which may be a similar material to that of the cores or of an ultra-hard material of a different grade to that of the first coating. The composite material typically takes on a honeycomb structure of a hard material and cores within the pores of the honeycomb structure bonded to the honeycomb structure. The pores of the honeycomb structure may be ordered or random.

Abstract: A boron suboxide composite material having improved fracture toughness consists of particulate or granular boron suboxide distributed in a binder phrase, such as AlxByOz, for example.

Abstract: The invention relates to a method for manufacture of diamond, the method including the steps of providing a first coating of solvent metal or solvent metal alloy on a diamond seed to create a coated diamond seed, situating the coated diamond seed adjacent a catalyst system comprising a solvent metal and/or a source of carbon, and subjecting the coated diamond seed and catalyst system to increased temperature wherein the melting point of the first coating is at least 20 deg C. below that of the catalyst system. The invention further relates to a compact comprising a plurality of diamond seeds wherein at least one seed includes a first coating comprising a solvent metal and/or solvent metal based alloy, the compact further comprising a catalyst system comprising a solvent metal and/or a source of carbon wherein the melting point of the first coating is at least 20 deg C. below that of the catalyst system.

Abstract: A method of coating ultrahard abrasive particles having vitreophilic surfaces, or treated to render their surfaces vitreophilic, are coated with an oxide precursor material, which is then heat treated to dry and purify the coats. The heat treated, coated ultrahard abrasive particles are further treated to convert the coats to an oxide, nitride, carbide, oxynitride, oxycarbide, or carbonitride thereof, or an elemental form thereof, or a glass.

Abstract: A component that is rigid and three-dimensional and has a relatively low mass. The component has a foil body formed of a metal or metal alloy matrix that is embedded with ultra-hard particles or grit, such as diamond and/or cBN. It can be used in applications where a combination of high rigidity and low mass is required, such as in audio applications, for example.

Abstract: A method of manufacturing polycrystalline abrasive elements consisting of micron, sub-micron or nano-sized ultrahard abrasives dispersed in micron, sub-micron or nano-sized matrix materials. A plurality of ultrahard abrasive particles having vitreophilic surfaces are coated with a matrix precursor material and then treated to render them suitable for sintering. The matrix precursor material can be converted to an oxide, nitride, carbide, oxynitride, oxycarbide, or carbonitride, or an elemental form thereof. The coated ultrahard abrasive particles are consolidated and sintcred at a pressure and temperature at which they are crystallographically or thermodynamically stable.

Abstract: A cubic boron nitride cluster comprises a core (10) and an overgrown region, the overgrown region containing a plurality of cubic boron nitride crystallites (12) extending outwards from the core (10). The majority of the cubic boron nitride crystallites (12) have a cross-sectional area which increases as the distance from the core (10) increases. A method of producing cubic boron nitride clusters is also provided.

Abstract: A method of producing a plurality of discrete ultra-hard abrasive particles includes the steps of providing a plurality of granules, each comprising at least one ultra-hard abrasive particle, a precursor for the abrasive particle and a solvent/catalyst for the abrasive particle or precursor of such a solvent/catalyst, placing the granules with a separating medium between adjacent granules in the reaction zone of a high pressure/high temperature apparatus, subjecting the contents of the reaction zone to elevated temperature and pressure conditions at which the ultra-hard abrasive particle is crystallographically stable, recovering thus treated material from the reaction zone and removing the separating medium in the treated material to produce a plurality of discrete abrasive particles.

Abstract: An abrasive product which comprises a polycrystalline mass of self-bonded abrasive particles of irregular shape, the product being substantially free of a second phase and containing substantial plastic deformation of the abrasive particles. The abrasive particles are preferably diamond or cubic boron nitride and the plastic deformation of the particles is preferably at least 0.3 percent. The abrasive product may be made by subjecting a mass of the particles to elevated temperature and pressure conditions.

Abstract: The invention provides a mass of crystals, particularly diamond crystals, having a size of less than 100 microns and in which mass the majority of the crystals are faceted single crystals. The invention further provides a method of producing such a mass of crystals which utilizes crystal growth under elevated temperature and pressure conditions, the supersaturation driving force necessary for crystal growth being dependent, at least in part, on the difference in surface free energy between low Miller index surfaces and high Miller index surfaces of the crystals. Preferably, the method is carried out under conditions where the Wulff effect dominates.