Sintered sol gel alumina abrasive filaments
AssigneeNorton Company
InventorsCharles V. Rue, Ronald H. van de Merwe, Ralph Bauer, Scott W. Pellow, Thomas E. Cottringer, Richard J. Klok
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Abstract
A filament shaped sintered alumina based abrasive made up predominantly of fine alpha alumina crystals.
Claims24
A sintered sol gel alumina based filament comprised of sintered alpha alumina crystals having a size no greater than 1 micron, said particles having a substantially uniform cross-section, a diameter not greater than 2 mm, an average aspect ratio of at least about 1.0 and a hardness of at least 16 Gpa.
A sintered, sol-gel, filament-shaped alumina-based, abrasive particle having a substantially uniform cross-section, a diameter corresponding to grit size of 16 or smaller, a hardness of at least 18 GPa, and an aspect ratio of from 1:1 to 8:1, which is comprised of at least 80% of equiaxed alpha alumina crystals with a crystal size of no greater than 1 micron.
A sintered sol-gel filament comprised of sintered alpha alumina crystals having a size no greater than micron, said filaments being substantially free of glassy components and having a substantially uniform cross-section and a hardness of at least 16 GPa and has a breaking strength of at least 8,000 kg/cm.sup.2.
A method of making a sintered filament shaped alumina based abrasive containing alpha alumina crystals, said alpha alumina crystals having a size of about 1 micron or less, comprising the steps of:
- providing a gelled dispersion of submicron hydrated alumina particles;
- shaping said gelled dispersion into filaments;
- drying the filaments;
- firing said dried filaments to a temperature between 1090.degree. C. and 1500.degree. C. for a time selected to convert the alumina in said filaments to a ceramic body, the major portion of which is made up of alpha alumina crystals of about 2 micron or less in size.
Dependencies are inferred from the claim text.