US Patent 7662735 Ceramic fibers and composites comprising same

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.