Abstract: An improved grinding wheel employing premium abrasive (diamond or cubic boron carbide) is made by employing a metal bond made from aluminum, zinc, copper, and tin, and including up to 50% of a dry film lubricant filler. The abrasive elements produced are particularly useful to form cup wheels for the dry grinding of carbide and tool steel.

Abstract: Iron or other magnetic metal powder is incorporated with aluminum in the core of a diamond or boron nitride grinding wheel. In addition to providing such characteristics as satisfactory bonding ability, strength, thermal expansion, thermal conductivity and turning characteristics, such cores are better held on a magnetic chuck for the performance of finishing operations.

Abstract: A diamond or cubic boron nitride grinding wheel in which an abrasive section comprising abrasive grits distributed through and held by a phenolic resin matrix is bonded to a non-abrasive core, is improved, in terms of ease of manufacture and elimination of cracking or poor adhesion, by means of a core composition which includes between 5 and 20% by volume of a thermoset resin selected from the group consisting of phenol aldehyde, urea formaldehyde, and melamine formaldehyde resins, particulate metal and graphite, and the remainder being a resin selected from the group consisting of epoxy resins, addition polymers of unsaturated polyesters, and thermosetting polyimide resins, in the range of from 5 to 80% by volume of the core.