The first choice for sand blasting is brown corundum with uniform particle size and guaranteed quality. Some of the white aluminium oxide used in industrial production is a fixed model, for example, the ceramic grinding wheel must be grade I brown corundum, grade II can not meet the use standard, and the grinding wheel is cracked and the hardness is not up to the standard. The first grade brown corundum is suitable for precision casting, wear-resistant materials and other industries with high abrasive requirements.
In other words, the final product of fused corundum can only be obtained through coarse crushing, medium crushing, crushing, segmented screening, magnetic separation, fine screening and other links. At present, as an abrasive, the chemical composition, particle size composition, magnetic content and particle density of fused corundum have national standards. When selecting, the fused Brown alumina is cooled, divided, crushed, air selected, we should strictly refer to national standards and select high-quality materials.
The fixed furnace melting block method and the dump furnace smelting method are generally used in the production of brown corundum at home and abroad. The two different production methods have their own advantages. The black corundum products produced by the dump furnace smelting method have good transparency, small crystal size and many combinations, so the flexibility is not good Because of its brittleness, the brown corundum crystal is easy to fall off.
The different smelting methods of brown corundum at home and abroad are mainly restricted by the factors of industrial structure and raw materials. It has the advantages of good density and sharpness and can be used in refractories and consolidation abrasives. The market covers Asia and Europe More than 150 countries and regions, such as Asia and the Americas, have been ranked first in the world in terms of export volume for many years.
Driven by the market demand, China's refractory industry is developing rapidly, the level of production technology and equipment is constantly improving, the quality of products is constantly improving, and the variety structure is constantly improving. So far, the variety and total amount of pink corundum refractory products in China not only meet the needs of domestic high-temperature industrial production and development, but also the export volume is increasing year by year.
The raw material is aluminum ash waste; the aluminum ash waste is washed with water until the pH value of the cleaning water is 6-7; the water content of the lost aluminum ash waste is dried to less than 1% at the temperature of 200-800 ℃; the dried aluminum ash waste is mixed with 0.5-1% of the Brown Alumina crystal seeds with the weight of the dry aluminum ash, and then melted at the temperature of 1900-2500 ℃; magnetically selected Brown corundum powder is prepared by sieving and other processes.