Alumina fused

In 1989, 164,200 t of regular fused alumina abrasive and 30,630 t of high purity fused alumina were produced in the United States and Canada, valued at U.S. 62.3 and 19.4 million, respectively (20). 

A higher density sol—gel abrasive, produced by the introduction of seed crystaUites formed by wet-milling with high alumina media or by introduction of submicrometer a-alumina particles, was patented (28) and designated Norton SG. The microstmcture of this abrasive consists of submicrometer a-alumina crystals (Fig. 1) and its bulk density approaches that of fused alumina. Norton SG has proven to be an exceptional performer in coated and bonded abrasive products it was awarded the 1989 ASM Engineering Materials Achievement Award (29). 

Aluminum Industry. Large amounts of HE are consumed in the production of aluminum fluoride [7784-18-17, AIE, and cryoHte [15096-52-3] (sodium aluminum fluoride), used by the aluminum industry. Both of these compounds are used in the fused alumina bath from which... 

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. 

There are on the market a number of bricks made from electrically fused materials, such as fused muUite, fused alumina, and fused magnesite. These bricks, although high in cost, are particularly suitable for certain severe conditions. 

Alumina, 2 345t 5 582. See also Activated alumina Aluminum oxide (alumina) Bauxite(s) Calcined alumina Fused alumina Tabular alumina in the activated catalyst layer, 10 41 adsorption capacity vs. years of service, 1 630... 

Fusarium graminearium, 11 4 Fusarium oxysporum, 13 351 Fused alumina, 1 2, 5-6... 

Aloxite. A trade name for an abrasive prepd by fusing alumina (bauxite) In an electric furnace ... 

Corundum is an aluminum oxide that possesses a hexagonal crystal structure, The compound is extremely hard (2000 on the Knoop scale), sp gr 3.95, and is widely used in abrasives and refractories. Corundum is manufactured by fusing alumina or bauxite in an electric arc furnace operated at about SIOO C. 

SiC, a hard substance(Moh s hardness 9.17), which can be obcained by heating sand and coke. with some sawdust in an electric furnace at high temp. The name carborundum is also applied to other hard materials, such as fused alumina. These materials are used as abrasives for cutting, grinding or polishing(Refs 2,3,5,6 7). 

A variety of thermocouples are available (Table 10.8), suitable for different measuring applications, and they are usually selected for the temperature range and sensitivity needed, for chemical inertness, and for magnetic properties (usually undesirable). They have been given alphabetic identifiers that have been accepted industry-wide. The B-, R-, and S-type thermocouples have low sensitivities and low resolutions the S type thermocouple is partially sheathed with a tube of fused alumina. The thermocouple types... 

Alumina is traditionally formed via thermal dehydration of aluminum hydroxides [94,95]. The final size and crystallinity of the alumina abrasives largely depend on the temperature and time of the thermal treatment process. It has been reported that the total reaction conversion occurs at a temperature of 1500 K. Technical grades of calcined alumina are commonly used for smelting, ceramics, and abrasive particles. Other common forms of alumina produced are fused and white tabular alumina. Fused alumina is produced by melting calcined alumina at a high-temperature furnace for extended time periods. White tabular alumina is composed of large well-developed crystals of... 

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