Zirconia fused

Mixed zircon, coke, iron oxide, and lime reduced together produce zirconium ferrosiUcon [71503-20-3] 15 wt % Zr, which is an alloy agent. Fused zirconia [1314-23-4] has been made from zircon but baddeleyite is now the preferred feed for the production of fused zirconia and fused alumina—zirconia by electric-arc-fumace processing. 

Zirconium oxide is fused with alurnina in electric-arc furnaces to make alumina—zirconia abrasive grains for use in grinding wheels, coated-abrasive disks, and belts (104) (see Abrasives). The addition of zirconia improves the shock resistance of brittle alurnina and toughens the abrasive. Most of the baddeleyite imported is used for this appHcation, as is zirconia produced by burning zirconium carbide nitride. 

Coated abrasives consist of a flexible backing on which films of adhesive hold a coating of abrasive grains. The backing may be paper, cloth, open-mesh cloth, vulcanized fiber (a specially treated cotton rag base paper), or any combination of these materials. The abrasives most generally used are fused aluminum oxide, sol-gel alumina, alnmina-zirconia. silicon carbide, garnet, emeiy, and flint. 

Table VIII presents analytical data for other nitrided catalysts (two fused and one precipitated) after use in the synthesis with 1H2 + ICO gas. The fused catalysts containing alumina (D3008) and zirconia (L3028) as structural promoters were more resistant to oxidation during synthesis at 21.4 atm. than was the catalyst promoted with magnesia (D3001). Nitrogen was removed more rapidly from the catalyst containing alumina (D3008) during synthesis at 21.4 atm. than at 7.8 atm. The analyses of catalyst P3003.24 indicate that nitrided, precipitated catalysts are also resistant to oxidation.

Grade Reagent, technical, crystals, fused, whiskers, CP (99% zirconia), hydrous. The fused grade is reported to be harder than diamond (11 on Mohs scale). 

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