The invention relates to a batch composition for producing a refractory product, a method for producing a refractory product, a refractory product, and to the use of a synthetic raw material.

An abrasive particle includes at most three surfaces and at least one edge which has a corner at at least one end. The abrasive particle may contain a ceramic material, particularly polycrystalline -Al.sub.2O.sub.3. Abrasive particles as a whole, methods for producing abrasive particles, moulds, abrasive articles, methods for producing abrasive articles, and methods for abrading a surface are also disclosed.

A method for manufacturing microfibrillated cellulose, a particulate grinding medium suitable for use in said method, a material which wears rough, and a method for making said particulate grinding medium.

A method of making abrasive particles includes: providing a slurry comprising non-colloidal solid particles and a liquid vehicle; forming at least a portion of the slurry into shaped bodies contacting a substrate; at least partially drying the shaped bodies to provide shaped abrasive precursor particles; separating at least a portion of the shaped abrasive precursor particles from the substrate; and converting at least a portion of the shaped abrasive precursor particles into shaped abrasive particles. The shaped abrasive particles comprise alpha alumina having an average crystal grain size of 0.8 to 8 microns and an apparent density that is at least 92 percent of the true density. Each shaped abrasive particle has a respective surface comprising a plurality of smooth sides that form at least four vertexes. Shaped abrasive particles, abrasive articles including them, and methods of using are also disclosed.

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 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.

A shaped ceramic abrasive particle, in particular on the basis of alpha-Al.sub.2O.sub.3, includes at least three faces, at least two faces of which form a common vertex on which at least one corner common to the three faces lies. The abrasive particle has at least one structural weakening element. The disclosure also relates to an abrasive article including the abrasive particles, and a method for producing the abrasive particles.

The present disclosure provides processes for forming angular ceramic particles. In at least one embodiment, a process for forming angular ceramic particles includes providing a slurry having a ceramic raw material having alumina. The process includes atomizing the slurry into droplets and coating seeds comprising alumina with the droplets to form green pellets. The process includes sintering the preen pellets to form sintered pellets. The process includes breaking the sintered pellets to form the angular ceramic particles comprising a sintered ceramic material. The angular ceramic particles can have an abrasion loss that is less than that of angular ceramic particles formed by crushing the green pellets prior to sintering.

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 proppant may include a sintered ceramic, wherein the sintered ceramic has a composition including an alumina (Al.sub.2O.sub.3) content ranging from about 60% to about 78% by weight, an iron oxide (Fe.sub.2O.sub.3) content ranging from about 5% to about 20% by weight, a silica (SiO.sub.2) content ranging from about 1% to about 10% by weight, a titania (TiO.sub.2) content ranging from about 2% to about 8% by weight, and a combined iron oxide and titania content of at least about 11% by weight. A proppant may include a sintered ceramic. The sintered ceramic may have a composition including a calcium oxide (CaO) content ranging from about 1% to about 5% by weight. A rod-shaped proppant may include a sintered ceramic having an aspect ratio ranging from about 1.5 to about 3, an apparent specific gravity ranging from about 2.0 to about 4.0, and a pack porosity of greater than 49%.