There are three main smelting methods for brown aluminum oxide smelting: fixed furnace smelting method, dumping furnace smelting method and exile smelting method. Due to the large investment scale of exile smelting, the fixed furnace smelting method and dumping furnace smelting method are mainly used at present.
Comparison of corundum products smelted by different methods:
1. The corundum produced by the dumping furnace (method) has many crystal aggregates, small crystal size, high glass phase and is distributed on the grain boundary, so the toughness is poor, the brittleness is large, the abrasive grains are easy to fall off, the self-sharpening is good, and the compactness is good. More suitable for consolidated abrasives and refractory materials.
2. The corundum produced by the frit furnace (method) has few crystal aggregates, large crystal size, and little glass quality, so it has poor brittleness, high toughness, and good wear resistance. Due to the large crystals, good toughness and brittleness, the brown fused alumina produced by this smelting method is more suitable for the manufacture of coated abrasives. Therefore, it is still the most widely used abrasive in the production of abrasive belts.
3. The chemical composition, phase composition and specific gravity of the corundum produced by the stream smelting method are equivalent to those produced by the frit method. Crystal size, microhardness, crystal structure, and compressive strength were slightly lower for the exile method than for the frit method. This is because the brown corundum produced by the exile method has the characteristics of microcrystalline corundum in these aspects. Although it is slightly lower than the frit method, it shows better results in use.
Production and application comparison of corundum smelted by different methods:
1. Exile hair: continuous production, high degree of automation, but large investment, complex structure, suitable for high-power smelting.
2. Dumping method: continuous production, high degree of mechanization, small investment, good production efficiency, a method that is widely used at present.
3. Fixing method (frit method): intermittent production, low degree of mechanization, but small investment, simple equipment and convenient process. It is the main method for corundum smelting in small abrasive factories at present.
