Abstract: Superabrasive grits such as diamond or CBN is chemically bonded with a coating such as tungsten which is in turn bonded to a tool body providing superabrasive cutting tools such as saw blades, grinding wheels, drill bits and the like.

Abstract: A friable silicon nitride body is prepared by infiltrating a non-friable silicon nitride body with a fluid which expands upon freezing, rapidly freezing the fluid, and thawing the frozen fluid. Silicon nitride flakes and chunks obtained with only light pressure on the friable body may then be final milled to a desired particle size more rapidly and with less energy input than with conventionally processed silicon nitride. The silicon nitride body may have a higher density than has previously been used to prepare silicon nitride powders, thereby preventing the generation of potentially hazardous whiskers in the final powder product.

Abstract: An improved abrasive product such as a grinding wheel is disclosed. The abrasive product contains an active filler mixture of tin, FeS.sub.2, and K.sub.2 SO.sub.4, which mixture improves the grinding quality and versatility of the abrasive product.

Abstract: Skis of laminated construction are assembled by joining the several lamellae with a hot melt adhesive which preferably contains an effective amount of an adhesion promoting agent. The hot melt adhesive is preferably a linear polyester, polyesteretheramide, polyetherester, polyamide, polyetherurethane, copolymer of ethylene-vinylacetate, polyesteramide, or polyetheramide, and when the adhesive is based on a copolymer, it is more preferable still that the copolymer is a block copolymer.

Abstract: To prevent thermal stress from damaging a PCD or diamond, multilayer metal coatings for bonding polycrystalline diamond compacts and diamond crystals to a matrix comprise a first metal layer of a refractory metal, such as tungsten, a compliant metal layer of copper, and an outer metal layer of a refractory metal such as tungsten. Metallic bonding layers of a metal, such as nickel, are placed between the tungsten and copper layers for improved bonding. The method of manufacturing multilayer metal coatings comprises applying the inner metal layer by chemical vapor deposition, applying the first bonding layer metal by electrolytic deposition, applying the compliant layer metal by electrolytic deposition, applying the second bonding layer by electrolytic deposition and applying the outer layer by chemical vapor deposition. A superabrasive tool element comprises a coated diamond product bonded either to a matrix comprising tungsten carbide or iron powder or to a cemented tungsten carbide support.

Abstract: The present invention is an electrical device made up of a mixture of silicon carbide and molybdenum disilicide, and may include silicon nitride or aluminum nitride or boron nitride. An electrical device is also disclosed which is particularly suited for use as an igniter in liquid and gas fuel burning systems. The device is made up of a sintered, preferably hot-pressed, mixture of fine powders of aluminum nitride or silicon nitride, silicon carbide and molybdenum disilicide where, when all three are present, they are present in substantial quantities.

Abstract: Abrasive article using sintered sol-gel abrasive particles mixed with other particles having greater friability, and carried in a bond.

Abstract: Resinoid and vitrified bonded abrasive products containing filament shaped sintered alumina based abrasive made up predominantly of fine alpha alumina crystals.

Abstract: A process for producing dry substantially crack-free shaped bodies, such as grinding wheels, from a sol-gel alumina hydrate composition is disclosed. The shaped bodies are formed by either a one or a two step forming process and avoid having to pre-prepare alpha alumina grits. The addition of specific crack-avoiding drying control additives, e.g. whiskers, chopped fibers, agarose gels, and formamide, to the sol-gel alumina hydrate prior to water removal therefrom substantially prevents crack-formation during the water removal operation.

Abstract: An improved temperature stable synthetic polycrystalline diamond (PCD) product includes at least one temperature stable PCD integrally and chemically bonded to a matrix carrier support through a carbide forming layer which is of a thickness of at least about 1 micron, the layer on at least one surface of the PCD is in turn bonded to the matrix carrier. A wide variety of shapes, sizes and configurations of such products is achieved through relatively low temperature and relatively low pressure processing. Various products of various geometries are described as well as the details of the processing to achieve chemical bonding of the PCD elements in a variety of support matrix carrier materials to form a unitary structure having a temperature stability up to about 1,200 degrees C.

Abstract: Multiple metal coated diamond grit for improved retention in a tool matrix comprises a first layer coating of a metal carbide of a strong carbide former, preferably chromium, titanium or zirconium, chemically bonded to the diamond and a second metal coating of an oxidation resistant carbide former, preferably tungsten or tantalum, chemically bonded to the first metal layer. A third metal layer coating of an alloying metal, preferably nickel, can also be added. In accordance with the method of the present invention, the first layer metal can be applied by metal vapor deposition. The second layer metal can be applied by chemical vapor deposition. The third layer of an alloying metal can be applied by electroless or electrolytic plating.

Abstract: Chrome oxide refractory materials which are a mixture of coarse fused chrome oxide particles and fine chrome oxide particles are disclosed as resistant to silica attack. The refractory materials have a Cr.sub.2 O.sub.3 content of at least about 98.5% and substantially no MgO.

Abstract: Coated abrasive material for fine finishing applications including second fining ophthalmic application, having patterned surface coating of abrasive grains dispersed in radiation-cured adhesive binder. The patterned surface coating is defined by a plurality of formations of such abrasive/binder each having an inner bottom edge defining an area devoid of coated abrasive, a top edge defining a somewhat larger area devoid of coated abrasive and an inner wall connecting the top and bottom edges.

Abstract: Superabrasive cutting elements, backed compacts and methods for their manufacture are disclosed wherein metal coated superabrasive particles are cemented under HPHT conditions. The superabrasives bond to the metal of the coating and the metal coatings of adjacent particles bond to each other forming a matrix. A binding aid with thermal expansion characteristics close to that of the superabrasive particle can be infiltrated through or otherwise mixed with the particles to assist in the bonding between the metal coatings and to fill in voids. Catalyst and non-catalyst binding aids can also be used. Uncoated, smaller superabrasive particles can be interstitially dispersed among the coated particles to increase the superabrasive concentration and can self bond to form a cemented/sintered structure. Tungsten is a preferred metal coating and silicon is a preferred binding/sintering aid. The superabrasive can be diamond, cubic boron nitride, boron doped diamond or crushed sintered polycrystalline aggregates.

Abstract: A single step fining pad for use in a ophthalmic applications having radiation cured maker and size coats of different hardnesses.

Abstract: A filament shaped sintered alumina based abrasive made up predominantly of fine alpha alumina crystals.

Abstract: An improved chromia-magnesia refractory product of co-fused chromia-magnesia grains bonded by an in situ formed chromia bond is prepared by substantially avoiding the presence of grains that will pass through a screen with openings of 150 microns. The resultant product exhibits improved resistance to silicieous materials such as are present in coal slags.

Abstract: Coated abrasive material having blends of abrasive grains of sol gel process alumina and alumina-zirconia in a volume ratio of at least 15% sol gel abrasive grain provide improved performance in certain grinding applications and a more universal coated abrasive product for a wider range of grinding applications than such products of either abrasive grain alone.

Abstract: Finely divided silicon carbide materials, particularly powders, whiskers and short fibers, are provided with a titanium nitride surface coating by the process of (i) placing a low carbon diffusivity layer atop the silicon carbide, (ii) placing a titanium metal coating atop the low carbon diffusivity layer, and (iii) nitriding the titanium metal.

Abstract: Strong and durable silicon nitride filtration membranes with effective separating layers having effective pore diameters less than about 1 micron are produced by depositing a source of silicon onto a porous microfilter support, removing any liquid used in the depositing, and subjecting the silicon source to nitridation conditions. Suitable sources of silicon include silicon per se and silica. When silica is used, a suitable reducing agent is deposited therewith to reduce the silica to silicon in situ.