An abrasive article including a bonded abrasive having a body of a diameter of at least 260 mm and a volume of at least 20 cubic centimeters, the body also having a bond material including an inorganic material, abrasive particles having an abrasive particle size of at least 40 microns contained in the bond material, and a certain Homogeneity Factor.

An abrasive article including a bonded abrasive having a body of a diameter of at least 260 mm and a volume of at least 20 cubic centimeters, the body also having a bond material including an inorganic material, abrasive particles having an abrasive particle size of at least 40 microns contained in the bond material, and a certain Homogeneity Factor.

An abrasive article can include a body including a bond material, abrasive particles, and a plurality of pores, wherein the bond material can comprise a vitreous material. In one embodiment, an average particle size of the abrasive particles can be between 0.1 microns to 5 microns, and a porosity of the body may be between 40 vol % to 70 vol %, wherein the porosity may define an average pore size (D50) of at least 0.1 microns and not greater than 5 microns.

An abrasive article can include a body including a bond material, abrasive particles, and a plurality of pores, wherein the bond material can comprise a vitreous material. In one embodiment, an average particle size of the abrasive particles can be between 0.1 microns to 5 microns, and a porosity of the body may be between 40 vol % to 70 vol %, wherein the porosity may define an average pore size (D50) of at least 0.1 microns and not greater than 5 microns.

An abrasive rotary tool includes a tool shank defining an axis of rotation for the rotary tool, and an abrasive external working surface. The abrasive external working surface includes a resin, and a plurality of porous ceramic abrasive composites dispersed in the resin, the porous ceramic abrasive composites including individual abrasive particles dispersed in a porous ceramic matrix. At least a portion of the porous ceramic matrix comprises glassy ceramic material. A ratio of the average porous ceramic abrasive composite size to the average individual abrasive particle size is no greater than 15 to 1.

An abrasive rotary tool includes a tool shank defining an axis of rotation for the rotary tool, and an abrasive external working surface. The abrasive external working surface includes a resin, and a plurality of porous ceramic abrasive composites dispersed in the resin, the porous ceramic abrasive composites including individual abrasive particles dispersed in a porous ceramic matrix. At least a portion of the porous ceramic matrix comprises glassy ceramic material. A ratio of the average porous ceramic abrasive composite size to the average individual abrasive particle size is no greater than 15 to 1.

A sintered vitrified superfinishing grindstone is provided which is a sintered product which is obtained by compression molding of a mixed powder of: a sinterable vitrified binder composed of a powder of a borosilicate glass composition; hard abrasive grains; and soft abrasive grains; and which includes bonded portions formed by necking due to heat compression, between particles of the powder of the borosilicate glass composition which are in contact with each other; and wherein the sinterable vitrified binder contains from 94 to 100% by mass of a powder composed of a low-melting-point borosilicate glass composition containing from 35 to 55% by mole of SiO.sub.2; from 3 to 5% by mole of A1.sub.2O.sub.3; from 10 to 35% by mole of B.sub.2O.sub.3; and from 25 to 30% by mole of R.sub.2O+RO.

A sintered vitrified superfinishing grindstone is provided which is a sintered product which is obtained by compression molding of a mixed powder of: a sinterable vitrified binder composed of a powder of a borosilicate glass composition; hard abrasive grains; and soft abrasive grains; and which includes bonded portions formed by necking due to heat compression, between particles of the powder of the borosilicate glass composition which are in contact with each other; and wherein the sinterable vitrified binder contains from 94 to 100% by mass of a powder composed of a low-melting-point borosilicate glass composition containing from 35 to 55% by mole of SiO.sub.2; from 3 to 5% by mole of A1.sub.2O.sub.3; from 10 to 35% by mole of B.sub.2O.sub.3; and from 25 to 30% by mole of R.sub.2O+RO.

An abrasive rotary tool includes a tool shank a flexible planar section positioned opposite the tool shank. The flexible planar section forms a first abrasive external surface on a first side of the flexible planar section and a second abrasive external surface on a second side of the flexible planar section. The flexible planar section facilitates abrading, corners of a workpiece across multiple angles relative to the axis of rotation for the rotary tool through bending of the flexible planar section when the abrasive external surfaces are applied to a corner of the workpiece.

An abrasive rotary tool includes a tool shank a flexible planar section positioned opposite the tool shank. The flexible planar section forms a first abrasive external surface on a first side of the flexible planar section and a second abrasive external surface on a second side of the flexible planar section. The flexible planar section facilitates abrading, corners of a workpiece across multiple angles relative to the axis of rotation for the rotary tool through bending of the flexible planar section when the abrasive external surfaces are applied to a corner of the workpiece.