Today, let's compare the properties and differences between fused white corundum and fused brown corundum to understand the relationship between the two: how much is fused white corundum and fused aluminum chrome sand?
1. Fused brown corundum
Brown corundum uses natural bauxite as raw material, carbon (mainly coke) as reducing agent, and iron filings as settling agent (clarifier) to form ferrosilicon deposited on the bottom of the electric furnace.
Brown corundum is tan, generally Al2O3≥94.5%, SiO2≤3.5%, TiO2≤3.5%, Fe2O3≤1%. The mineral composition is mainly α-Al2O3. The central part of the crystal shape is rhombus, thick plate and particles with cracks. There are many silicon oxide and calcium oxide melt crystals around, which are long plate-like and Z-coarse grains. Skeletal platelets. Since the impurities have not been completely removed, brown corundum also contains secondary crystal phases such as calcium hexaaluminate, calcium plagioclase, spinel, and rutile, as well as glass phases, iron alloys, and solid solutions. The hue of brown corundum depends to a large extent on the titanium oxide remaining in the product.
How much is fused aluminum chrome sand
Brown corundum is mainly used as abrasive. In recent years, it has been used as an aggregate for large and medium-sized blast furnace tap hook castables and anhydrous tap mud, and as a raw material for making ordinary corundum bricks (including high-alumina silicon carbide).
2, fused white corundum
Now commonly referred to as "fused alumina" generally refers to "fused white corundum". It is made of calcined alumina or industrial alumina as raw material, which is melted at high temperature in an electric arc furnace. For elongated and rhombus, and often skeletal crystals. Since the raw material is very pure, no chemical reaction occurs in the electric furnace operation, but the temperature and cooling rate of the molten liquid have a great influence on the structure of the block material. In terms of homogeneity, it is important to obtain as dense a block as possible. When the Na2O in the raw material solidifies, β-Al2O3 is formed, which is easy to concentrate in the central part of the block, which will adversely affect the refractory and abrasive materials, so the content of Na2O in the raw material must be paid attention to. In addition, there is still a small amount of nepheline and glass in the block.