Abstract: Abrasive tools suitable for precision grinding of hard brittle materials, such as ceramics and composites comprising ceramics, at peripheral wheel speeds up to 160 meters/second are provided. The abrasive tools comprise a wheel core attached to an abrasive rim of dense, metal bonded superabrasive segments by means of a thermally stable bond.

Abstract: Abrasive tools suitable for precision grinding of hard brittle materials, such as ceramics and composites comprising ceramics, at peripheral wheel speeds up to 160 meters/second are provided. The abrasive tools comprise a wheel core attached to an abrasive rim of dense, metal bonded superabrasive segments by means of a thermally stable bond. A preferred tool for backgrinding ceramic wafers contains graphite filler and a relatively low concentration of abrasive grain.

Abstract: A method for precision cylindrical grinding of hard brittle materials, such as ceramics or glass and composites comprising ceramics or glass, provides material removal rates as high as 19-380 cm.sup.3 /min/cm. The abrasive tools used in the method comprise a strong, light weight wheel core bonded to a continuous rim of abrasive segments containing superabrasive grain in a dense metal bond matrix.

Abstract: A composite, polymer bonded abrasive wheel is disclosed for grinding operations and especially for use with multiple station, glass beveling machines. The abrasive wheel breaks in quickly and delivers consistent performance with little or no dressing needed over the entire life of the wheel. In one aspect, the novel abrasive wheel includes a concentrically mounted, annular abrasive rim on a cup shaped hub. The rim can contain an abrasive such as diamond or cubic boron nitride which is embedded in a bonding composition that includes amino aldehyde and phenolic thermoset polymers, a plasticizer, and optionally filler. The hub includes a crosslinkable, strong and rigid, engineering polymer, preferably melamine phenolic thermoset polymer, mixed with spodumene in amount effective to make the coefficient of thermal expansion of the hub match that of the rim. The wheel can be made by simultaneously hot pressing rim and hub preforms and without an additional baking step.

Abstract: The present invention is a metal bond comprising a filler with a Vickers hardness from about 300 kg/mm.sup.2 to about 800 kg/mm.sup.2 wherein the Vickers hardness of the filler is maintained above 300 kg/mm.sup.2 upon firing of the bond at a temperature above 700.degree. C. for at least about 10 minutes. The present invention further is an abrasive tool comprising a metal core; an abrasive composition comprising diamond and the above metal bond, bonded to the metal core.

Abstract: A composite grinding wheel comprising a support center with a peripheral groove containing a ring of metal bonded abrasive bonded thereto is made by placing in the bottom of an annular mold cavity, a ring whose internal bore is larger than and spaced from the inner smaller diameter of the mold cavity. The mold cavity above the ring is then filled with a sufficient volume of a mixture of metal bond and abrasive particles and closed off by an annular support center supported by the mold and having a central hub portion of smaller diameter than the internal bore in the ring and an axial height extending upwardly to an upper outer flange extending radially over the top of the mold cavity. The support center and ring are pressed together thereby compacting the mixture of metal bond and abrasive particles together between the upper outer flange and ring until the central hub extends into the ring and is substantially aligned with the bottom of the mold cavity and side of the ring.