Application field magnesia zirconium brick
Magnesia-chrome bricks are mainly used in the metallurgical industry, such as building open hearth furnace tops, electric furnace tops, refining furnaces outside the furnace and various non-ferrous metal smelting furnaces. The high-temperature part of the furnace wall of the ultra-high-power electric furnace of magnesia-chrome bricks adopts fused-cast magnesia-chrome bricks, the high-erosion area of the refining furnace outside the furnace adopts magnesia-chrome bricks made of synthetic materials, and the high-erosion area of non-ferrous metal flash smelting furnace adopts fused-cast magnesia-chrome bricks, Magnesia-chrome bricks made of synthetic materials. In addition, magnesia-chrome bricks are also used in the firing zone of cement rotary kilns and the regenerators of glass kilns.
The production process of fired magnesia-chrome bricks is generally similar to that of magnesia bricks. In order to eliminate the MgO and Cr2O3, Al2O3 or
magnesia zirconium brick
The loosening effect caused by the expansion of iron oxides to form spinel can also be made of magnesia-chrome bricks by using synthetic co-sintering materials. In addition, there are unburned magnesia chrome bricks, for example, unburned magnesia chrome bricks combined with inorganic magnesium salt solutions. The production process of unburned magnesia-chrome bricks is simple, the cost is low, and the thermal stability is good, but the high temperature strength is far less than that of fired bricks. In the late 1950s, a so-called "direct combination" magnesia-chrome brick was developed. The characteristics of this kind of brick are pure raw materials, high firing temperature, direct bonding between high temperature phases such as periclase and spinel, and low melting phases such as silicate are distributed in islands. Therefore, the high temperature of the brick is significantly improved. Strength and slag resistance.
The method of making bricks by co-grinding and calcining fine powder with chrome ore and magnesia and coarse particles of magnesia is an effective measure to eliminate the loosening effect. Compared with ordinary magnesia-chrome bricks, the magnesia-chrome bricks made by this method have lower porosity and higher compressive strength, softening temperature under load and flexural strength. The magnesia-chrome brick made of chrome ore-magnesite powder compacted and synthetic magnesia-chrome sand calcined at high temperature has better slag resistance and high-temperature strength than other magnesia-chrome bricks.
In addition, there are also fused-cast magnesia-chrome bricks that are directly cast by melting magnesia-chromium materials in an electric furnace (see the microstructure and color pictures). Chrome bricks, etc.