Abstract: A method of making sintered abrasive particles includes passing alumina precursor particles through a flame under conditions such that they are converted to alpha alumina. The precursor particles comprise a precursor of alpha alumina and have an average particle size of less than or equal to 500 microns. Sintered abrasive particles have a cellular microstructure comprising alpha alumina crystal grains of alpha alumina having a maximum dimension of less than about 3 microns are also disclosed. The sintered abrasive particles have an average particle size of less than or equal to 500 microns, and are essentially free of seed particles and alpha alumina grain size modifiers. Abrasive articles comprising a binder and a plurality of the sintered abrasive particles are also disclosed.

Abstract: 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.

Abstract: Glass-ceramics comprising Al2O3 and rare earth oxide, yttrium oxide, and/or alkaline earth oxide. Uses of the glass-ceramics include dental articles, orthodontic appliances, abrasive particles, cutting tools, infrared windows, and ceramic bearings.

Abstract: A molding operation produces an extractor array by providing a mold having a plurality of cavities therein, each cavity being adapted to form an extractor suitable for coupling to an LED die; filling the mold with a plurality of glass particles; heating the glass particles above glass transition temperatures thereof so that the particles are reshaped to conform to the cavity shapes; and forming a land layer that extends between the cavities. The land layer maintains the extractors in a fixed spatial relationship with each other for subsequent handling or processing, such as a simultaneous polishing operation or in attaching the extractor array to a corresponding LED array.

Abstract: Al2O3-rare earth oxide-ZrO2/HfO2 ceramics (including glasses, crystalline ceramics, and glass-ceramics) and methods of making the same. Ceramics according to the present disclosure can be made, formed as, or converted into glass beads, articles (e.g., plates), fibers, particles, and thin coatings. The particles and fibers are useful, for example, as thermal insulation, filler, or reinforcing material in composites (e.g., ceramic, metal, or polymeric matrix composites). The thin coatings can be useful, for example, as protective coatings in applications involving wear, as well as for thermal management. Certain ceramic particles according to the present disclosure can be are particularly useful as abrasive particles.

Abstract: Methods of melt spinning to make amorphous and ceramic materials.

Abstract: A moldable article, including at least a container made of a barrier material, the container providing an interior space within which a plurality of glass particles are contained. The glass has a glass transition temperature and a crystallization onset temperature, the difference between the glass transition temperature and the crystallization onset temperature is at least about 5° K., and the glass is composed of at least two metal oxides, from 0 to less than 20% by weight SiO2, from 0 to less than 20% by weight B2O3, and from 0 to less than 40% by weight P2O5. The moldable article protects the glass particles by keeping them clean and moisture free prior to a molding operation. A method of making a moldable article includes: removing entrapped moisture from a plurality of glass particles, placing glass particles in a receptacle, and sealing the receptacle to form the article.

Abstract: Disclosed herein is a ceramic comprising: at least two different metal oxides, the at least two different metal oxides comprising TiO2 and La2O3 or TiO2 and BaO; less than 20% by weight SiO2; less than 20% by weight B2O3; and less than 40% by weight P2O5; the ceramic having a glass transition temperature, Tg, and a crystallization onset temperature, Tx, and the difference between Tg and Tx is at least 5K. The ceramic may comprise additional metal oxides. Also disclosed herein is a method of making an article using the ceramic; typically, the ceramic is heated above the Tg, shaped, and then cooled.

Abstract: Presently described are retroreflective articles, such as pavement markings, that comprise transparent microspheres partially embedded in a (e.g., polymeric) binder. Also described are (e.g., glass-ceramic) microspheres, methods of making microspheres, as well as compositions of glass materials and compositions of glass-ceramic materials. The microspheres generally comprise lanthanide series oxide(s), titanium oxide (TiO2), and optionally zirconium oxide (ZrO2).

Abstract: Al2O3-rare earth oxide-ZrO2/HfO2 ceramics (including glasses, crystalline ceramics, and glass-ceramics) and methods of making the same. Ceramics according to the present disclosure can be made, formed as, or converted into glass beads, articles (e.g., plates), fibers, particles, and thin coatings. The particles and fibers are useful, for example, as thermal insulation, filler, or reinforcing material in composites (e.g., ceramic, metal, or polymeric matrix composites). The thin coatings can be useful, for example, as protective coatings in applications involving wear, as well as for thermal management. Certain ceramic particles according to the present disclosure can be are particularly useful as abrasive particles.

Abstract: A method for making an article from glass comprises providing a substrate including an outer surface; providing at least a first glass comprising at least two different metal oxides, wherein the first glass has a Tg and Tx, and wherein the difference between the Tg and the Tx of the first glass is at least 5K, the first glass containing less than 20% by weight Si02, less than 20% by weight B2O3, less than 40% by weight P2O5, and less than 50% by weight PbO; heating the first glass at or below ambient pressure to above its Tg such that at least a portion of the glass wets at least a portion of the outer surface of the substrate; and cooling the glass to provide an article comprising ceramic comprising the glass attached to the at least a portion of the outer surface of the substrate. The porosity of the ceramic is less than 20% by volume.

Abstract: Presently described are retroreflective articles, such as pavement markings, that comprise transparent microspheres partially embedded in a (e.g., polymeric) binder. Also described are (e.g., glass-ceramic) microspheres, methods of making microspheres, as well as compositions of glass materials and compositions of glass-ceramic materials. The microspheres generally comprise lanthanide series oxide(s), titanium oxide (TiO2), and optionally zirconium oxide (ZrO2).

Abstract: Presently described are retroreflective articles, such as pavement markings, that comprise transparent microspheres partially embedded in a (e.g., polymeric) binder. Also described are (e.g., glass-ceramic) microspheres, methods of making microspheres, as well as compositions of glass materials and compositions of glass-ceramic materials. The microspheres generally comprise lanthanide series oxide(s), titanium oxide (TiO2), and optionally zirconium oxide (ZrO2).

Abstract: Al2O3-rare earth oxide-ZrO2/HfO2 ceramics (including glasses, crystalline ceramics, and glass-ceramics) and methods of making the same. Ceramics according to the present invention can be made, formed as, or converted into glass beads, articles (e.g., plates), fibers, particles, and thin coatings. The particles and fibers are useful, for example, as thermal insulation, filler, or reinforcing material in composites (e.g., ceramic, metal, or polymeric matrix composites). The thin coatings can be useful, for example, as protective coatings in applications involving wear, as well as for thermal management. Certain ceramic particles according to the present invention can be are particularly useful as abrasive particles.

Abstract: Ceramic fibers comprising glass, and composites comprising such fibers. The glass comprises at least 35 percent by weight Al2O3, based on the total metal oxide content of the glass, a first metal oxide other than Al2O3, and a second, different metal oxide other than Al2O3. The glass contains not more than 10 percent by weight collectively As2O3, B2O3, GeO2, P2O5, SiO2, TeO2, and V2O5, based on the total weight of the glass. The first and the second metal oxides are each selected from the group consisting of Y2O3, REO, MgO, TiO2, Cr2O3, CuO, NiO, Fe2O3, ZrO2, HfO2 and complex metal oxides thereof. At least a portion of the glass may be converted to crystals.

Abstract: Method of making an article, the method comprising coalescing a plurality of the glass particles. The article may comprise glass, glass-ceramic, and/or crystalline ceramic. Examples of articles include kitchenware (e.g., plates), dental brackets, and reinforcing fibers, cutting tool inserts, abrasives, and structural components of gas engines, (e.g., valves and bearings).

Abstract: Ceramic materials and articles comprising at least 35 percent by weight Al2O3, and a plurality of cells having an average cell size of less than 3 micrometers.

Abstract: Presently described are retroreflective articles, such as pavement markings, that comprise transparent microspheres partially embedded in a (e.g., polymeric) binder. Also described are (e.g., glass-ceramic) microspheres, methods of making microspheres, as well as compositions of glass materials and compositions of glass-ceramic materials. The microspheres generally comprise lanthanide series oxide(s), titanium oxide (TiO2), and optionally zirconium oxide (ZrO2).

Abstract: Al2O3-rare earth oxide-ZrO2/HfO2 ceramics (including glasses, crystalline ceramics, and glass-ceramics) and methods of making the same. Ceramics according to the present invention can be made, formed as, or converted into glass beads, articles (e.g., plates), fibers, particles, and thin coatings. The particles and fibers are useful, for example, as thermal insulation, filler, or reinforcing material in composites (e.g., ceramic, metal, or polymeric matrix composites). The thin coatings can be useful, for example, as protective coatings in applications involving wear, as well as for thermal management. Certain ceramic particles according to the present invention can be are particularly useful as abrasive particles.

Abstract: Abrasive particles comprising ceramic (including glasses, crystalline ceramics, and glass-ceramics) comprising (on a theoretical oxide basis) Al2O3 and at least one other metal oxide (e.g., REO and; REO and at least one of ZrO2 or HfO2) and methods of making the same. The abrasive particles can be incorporated into a variety of abrasive articles, including bonded abrasives, coated abrasives, nonwoven abrasives, and abrasive brushes.