A shaped ceramic abrasive particle based on alpha-Al.sub.2O.sub.3 contains a proportion of 5% to 30% by weight of ZrO.sub.2. The alpha-Al.sub.2O.sub.3 has a medium crystallite size of 0.5 m to 3 m and the ZrO.sub.2 has a medium crystallite size of 0.25 m to 8 m.

A sintered rod-shaped proppant and anti-flowback agent possesses high strength and high conductivity. The sintered rods comprise between about 0.2% by weight and about 4% by weight aluminum titanate. In some embodiments, the sintered rods are made by mixing bauxitic and non-bauxitic sources of alumina that may also contain several so-called impurities (such as TiO.sub.2), extruding the mixture, and sintering it. The starting material may optionally be milled to achieve better compacity and crush resistance in the final sintered rod. A fracturing fluid may comprise the sintered rods alone or in combination with a proppant, preferably a proppant of a different shape.

A method of forming a shaped abrasive particle including extruding a mixture into a form, applying a dopant material to an exterior surface of the form, and forming a precursor shaped abrasive particle from the form.

A shaped abrasive particle including a body having a first major surface, a second major surface, and a side surface joined to the first major surface and the second major surface, and the body has at least one partial cut extending from the side surface into the interior of the body.

Disclosed is a composite abrasive with hard core and soft shell, comprising hard abrasive core with grain diameter in a range of 0.11 m and a soft oxide shell with thickness in a range of 5100 nm, the grain size of the oxide of the soft oxide shell is in a range of 520 nm, the composite abrasive is obtained from aqueous solution of oxide inorganic salt precursor and the hard abrasive by dispersing, constant temperature reflux hydrolyzing, solid-liquid separating, washing and drying. The component abrasive with hard core and soft shell of the present invention can improve the manufacturing efficiency and the surface quality during the ultraprecise manufacturing of the sapphire substrate.

Various shaped abrasive particles are disclosed. Each shaped abrasive particle includes a body having at least one major surface and a side surface extending from the major surface.

A shaped abrasive agglomerate particle includes a shaped abrasive particle bonded in a vitreous matrix. The shaped abrasive particles have a longest particle lineal dimension on a surface and a shortest particle dimension perpendicular to the longest particle lineal dimension, and the longest particle lineal dimension is at least twice the shortest particle dimension. The shaped abrasive agglomerate particle has a longest agglomerate lineal dimension on a surface and a shortest agglomerate dimension perpendicular to the longest agglomerate lineal dimension, and the longest agglomerate lineal dimension is at least twice the shortest agglomerate dimension. The abrasive agglomerate particles are useful in abrasive articles. Methods of making the shaped abrasive agglomerate particle and abrading a workpiece are also described.

A particulate material having a body including a dopant contained in the body, the dopant is non-homogenously distributed throughout the body and the body has a maximum normalized dopant content difference of at least 35%.

An abrasive grain includes a surface having at least a first face with a first outline, and at least one second face with a second outline. The first outline does not contain any vertices, but the second outline contains at least one vertex. The abrasive grain may include a ceramic material, especially polycrystalline -Al.sub.2O.sub.3.

A method for forming rod-shaped particles includes reducing a length of rods derived from a slurry made up of particles and a reactant, wherein the rods are in a stabilized state in which the reactant has been at least partially reacted with a coagulant, but the rods have not been sintered, and subsequently sintering the reduced length stabilized rods. The reducing the length of the stabilized rods includes subjecting the stabilized rods to mechanical vibration applied by a device, or feeding the stabilized rods through a device having a rotating cutting mechanism.