Abstract: Organic bonded abrasive tools, having controlled microstructures, comprise a relatively low volume percentage of abrasive grain and a relatively low hardness grade, but are characterized by the excellent mechanical strength and efficient grinding performance of much harder grade, lower porosity tools, especially in versatile grinding processes, such as centerless grinding. A method for centerless grinding with these tools is provided. Methods for making the abrasive tools utilizing agglomerated abrasive grain are described.

Abstract: A nozzle assembly and method is configured to apply coherent jets of coolant in a tangential direction to the grinding wheel in a grinding process, at a desired temperature, pressure and flowrate, to minimize thermal damage in the part being ground. Embodiments of the present invention may be useful when grinding thermally sensitive materials such as gas turbine creep resistant alloys and hardened steels. Flowrate and pressure guidelines are provided to facilitate optimization of the embodiments.

Abstract: A bonded abrasive tool, having a structure permeable to fluid flow, comprises sintered agglomerates of a plurality of abrasive grains and a binding material, the binding material being characterized by a melting temperature between 500 and 1400° C., and the sintered agglomerates having a loose packing density of ?1.6 g/cc and three-dimensional shape; a bond material; and about 35–80 volume % total porosity, including at least 30 volume % interconnected porosity. Methods for making the sintered agglomerates and abrasive tools containing the sintered agglomerates are described.

Abstract: Grinding of mill rolls is carried out with chatter resistant abrasive grinding wheels having relatively low elastic modulus values and relatively high burst speed values. Grinding operations may be carried out at high efficiency with controlled wheel vibration, thus generating optimum surface quality on the ground mill rolls.

Abstract: A method for producing organically bonded abrasive article includes combining an abrasive grain component and a phenol-based resin component. The combined components are molded and thermally cured in an atmosphere that comprises humidity, wherein the atmosphere contacts the molded components, thereby producing the organically bonded abrasive grain. The abrasive grain optionally can first be combined with an organosilicon compound, to form organosilicon-treated abrasive grain, and then with the phenol-based resin component. In one example, the phenol-based resin is thermally cured in the presence of steam. Abrasive articles produced by the method of the invention generally have improved properties under wet grinding conditions. In one example, an abrasive article produced by the method of the invention includes ammonia in an amount less than about 50 ppm. In another example, an abrasive grinding wheel produced by the method of the invention has a strength retention greater than about 57 percent.

Abstract: This invention relates to an abrasive cutting tool comprising: i) a substrate surface having a plurality of teeth extending therefrom, and ii) a single layer of abrasive grains chemically bonded to at least a portion of each tooth to define a plurality of cutting levels parallel to the substrate surface, the cutting levels comprising a first uppermost cutting level and a second uppermost cutting level, the grains having a predetermined concentration, size and toughness, whereby the abrasive cutting tool has a cutting surface with a negative angle of inclination with respect to an intended direction of cutting.

Abstract: This invention relates to a method of cutting, comprising the steps of: a) providing an abrasive cutting tool comprising: i) a substrate surface having a plurality of teeth extending therefrom, and ii) a single layer of abrasive grains chemically bonded to at least a portion of each tooth to define a plurality of cutting levels parallel to the substrate surface, the cutting levels comprising a first uppermost cutting level and a second uppermost cutting level, the grains having a predetermined concentration, size and toughness, b) moving the substrate surface in an intended direction of rotation, c) contacting the uppermost cutting level of at least one tooth to a workpiece at a point of contact, d) applying a constant force to the tool directed at the point of contact, wherein the constant force is sufficient to cut the workpiece, the strength of the bond is sufficient to resist peeling, the predetermined concentration, size and toughness of the plurality of grains are such that the grains of the uppe

Abstract: A flexible or semi-rigid support fixture is sized and shaped to supportably engage a surface of a polymeric matrix object such as an organic bonded abrasive grinding wheel. The support fixture is utilized to support the object to help prevent slumping and/or expansion during thermal curing operations. The fixture is fabricated from a material, such as silicone rubber, that is capable of withstanding heat commonly associated with thermal curing operations and which provides sufficient resilience to permit use with objects manufactured within a relatively wide range of dimensional tolerances. Suitable materials include silicone rubber or other polymers or copolymers such as PTFE, FEP, Polyimide or blends with or without fillers or substrates.

Abstract: A burr is provided for dressing a grinding tool, such as the grinding surface of a pulpstone grinding tool used for mechanical preparation of wood pulp. The burr includes a cylindrical body portion, a plurality of teeth disposed on and protruding outward from the outer surface thereof, and at least one annular channel formed in the outer surface thereof. The burr may provide for a more uniform dress pattern in a grinding surface of a pulpstone grinding tool to provide improved consistency and quality of wood pulp produced thereby.

Abstract: An abrasive wheel is used to separate individual laminated chips from a strip by cutting through the copper bridging elements. The abrasive wheel is made up of abrasive particles bonded in a matrix having a high glass transition temperature and a cutting edge having a maximum thickness of the order of 350 micron, whereby the cut is substantially straight and free of smears and burrs.

Abstract: The invention relates to an improved grinding wheel for grinding eye glass edges. The grinding wheel comprises a base member and an abrasive coating of diamond and metal. The base member 3 consists substantially of plastic material and an annular member 2 of metallic material is provided between the base member 3 and the coating 1. The metallic material of the annular member 2 has a strength withstanding the forces occuring in sintering the coating to the annular member.

Abstract: A method is provided for fabricating an abrasive article having porosity. The method includes blending a mixture of abrasive grain, bond material, and pore inducer, in which the pore inducer is soluble in a supercritical fluid, and the abrasive grain and bond material are substantially insoluble in the supercritical fluid. The mixture is pressed into an abrasive laden composite and exposed to the supercritical fluid for a period of time suitable to dissolve at least a portion of the pore inducer. The composite is thermally processed.

Abstract: A grinding tool and method is provided for shaping an edge of sheet glass. The grinding tool includes an arbor and a wheel being of a unitary construction and including an axis of rotation. The grinding tool further includes a recess extending along a periphery of the wheel, with a bonded abrasive being disposed therein. The bonded abrasive is sized and shaped for being profiled, to shape an edge of a glass sheet upon rotation of the tool about the axis. The bonded abrasive may further be sized and shaped for being re-profiled after use. The grinding tool of this invention may provide for both improved quality and reduced cost sheet glass.

Abstract: An abrasive article including from about 40 to about 80 volume percent interconnected porosity, the article being useful as a segment for a segmented grinding wheel, and a method for fabricating the same. The method includes blending a mixture of abrasive grain, bond material and dispersoid particles, the mixture including from about 40 to about 80 volume percent dispersoid particles. In one embodiment the mixture includes from about 50 to about 80 volume percent dispersoid particles. In another embodiment the mixture includes an organic bond material and from about 40 to about 80 volume percent dispersoid particles. The powder mixture is then pressed into an abrasive laden composite and thermally processed. After cooling the composite is immersed into a solvent, which dissolves substantially all of the dispersoid particles, leaving a highly porous, bonded abrasive article.

Abstract: The present invention provides a vitrified-bonded abrasive tool wherein the abrasive grit portion comprises a thermally sensitive abrasive grain, such as sintered sol gel microcrystalline alpha alumina abrasive grain or superabrasive grain, and wherein the vitrified bond may be matured by firing at a temperature of about 700 to 1,100 ° C. The invention preferably is carried out with sintered sol gel microcrystalline alpha alumina abrasive grain and a phosphorous oxide-containing, alkaliborosilicate vitrified bond composition. In one embodiment, during firing at about 700 to 1,100 ° C., the vitrified bond of the invention comprises at least two immiscible, amorphous phases.

Abstract: An abrasive article including from about 40 to about 80 volume percent interconnected porosity, the article being useful as a segment for a segmented grinding wheel, and a method for fabricating the same. The method includes blending a mixture of abrasive grain, bond material and dispersoid particles, the mixture including from about 40 to about 80 volume percent dispersoid particles. In one embodiment the mixture includes from about 50 to about 80 volume percent dispersoid particles. In another embodiment the mixture includes an organic bond material and from about 40 to about 80 volume percent dispersoid particles. The powder mixture is then pressed into an abrasive laden composite and thermally processed. After cooling the composite is immersed into a solvent, which dissolves substantially all of the dispersoid particles, leaving a highly porous, bonded abrasive article.

Abstract: A bonded abrasive tool, having a structure permeable to fluid flow, comprises sintered agglomerates of a plurality of abrasive grains and a binding material, the binding material being characterized by a melting temperature between 500 and 1400° C., and the sintered agglomerates having a loose packing density of ≦1.6 g/cc and three-dimensional shape; a bond material; and about 35-80 volume % total porosity, including at least 30 volume % interconnected porosity. Methods for making the sintered agglomerates and abrasive tools containing the sintered agglomerates are described.

Abstract: A nozzle assembly and method is configured to apply coherent jets of coolant in a tangential direction to the grinding wheel in a grinding process, at a desired temperature, pressure and flowrate, to minimize thermal damage in the part being ground. Embodiments of the present invention may be useful when grinding thermally sensitive materials such as gas turbine creep resistant alloys and hardened steels. Flowrate and pressure guidelines are provided to facilitate optimization of the embodiments.

Abstract: A process for metal coating diamond superabrasive particles involves heating the superabrasive particles in the presence of coat-forming powder of a metal compound under a common inert atmosphere. The metal compound contains a metal which can be thermochemically reduced by the superabrasive substance serving as the reducing agent. The process forms a chemical bond at the interface between the outer metal layer and the superabrasive particle substrate. The metal coated superabrasive particles can be hydrogen treated in situ and separated from excess coat-forming powder easily by filtration. The product particles are ideal for use in a wide variety of metal bonded cutting, machining, dressing and other abrasive tools, especially diamond film insert and single layer diamond tools.

Abstract: Methods for orienting fibers and an apparatus for orienting fibers are provided for the fabrication of improved thin abrasive wheels utilizing uniform non-woven fiber reinforcement discs. The wheels are more resistant to hub push-out failure during grinding than wheels reinforced with woven fiber cloth.