Corundum mullite brick.

Corundum mullite brick is commonly known as white iron brick or fused cast zirconium corundum brick. It is the guarantee for normal operation of the glass furnace refractory materials, the most important current glass furnace at home and abroad to improve fusion rate, extend the kiln age, reduce fuel consumption is mainly due to the use of the refractory to realize.

Zirconia corundum brick is also known as corundum - zircon products, its main chemical composition Al2O3 is 50%, and ZrO2 is 20% and 40%, and the rest is SiO2. The main minerals consist of zircon (ZrO2), corundum (alpha-al2o3) and glass phase. The zircon crystals form the backbone of the brick, the ZrO2 melting point is high (2715), the chemical stability is good, and the acid, alkaline medium and especially the resistance to the glass solution is strong. Zirconium fused corundum brick with the increase of ZrO2 content, its performance increases, general zirconium corundum brick according to how much the amount of ZrO2 can be divided into several levels, such as containing 33%, 36% and 41% levels, there are divided into containing 30%, 40 x, 50% of the grade, it is not unified. Currently in use is more inclusive of our 33% zirconium products, its density is 3.65 3.7 g/cm3, the highest temperature about 1700 ℃. Electrofused zirconium corundum bricks are used in glass melting furnace and other industrial furnaces. The parts used in glass melting furnace are masonry wall, small furnace, small furnace stack, tongue and chest wall etc. The following problems should be noted in use. (1) thermal expansion of the expansion of the irregular change zirconium fused corundum brick curve has a near 1000 ℃ is unusual, the reversibility of ZrO2 crystals occur within the crystal transformation, has a larger volume change, therefore, products containing ZrO2 is unfavorable use at about 1000 ℃ temperature often volatile. Oven baking furnace, the temperature changes during 900 ~ 1150 ℃ cannot too big, generally no more than 15 ℃ / h, request smoothly. Some parts should be protected from blowing cold, and other bricks should be used to protect them from bursting. (2) the shrinkage of casting molding, casting shrinkage cavity mouth often appear, brick here blowhole is more, the density difference, so in the build by laying bricks or stones of glass melting pool wall, both the shrinkage cavity in the direction of the stove, if the sprue outwards, when bricky system into the very thin, can cause leaks glass accident. When used in the upper flame space of the pool kiln, the service life is very long and there is no problem of running glass liquid. Therefore, it is used to extend the service life. (3) eutectic fused zirconium corundum brick contact with clay brick masonry, eutectic phenomenon will happen under the high temperature of 1300 ℃, thus, when choosing refractory, should avoid eutectic phenomenon serious two contact masonry of refractory material and silica as below the zirconium fused corundum brick, zirconium are most vulnerable to fused corundum brick of erosion. The zirconia corundum products of glass kiln are divided into three grades according to their zirconia content. Azs-33: the content of zirconium oxide is 33%; Azs-36: the content of zirconium oxide was 36%; Azs-41: the content of zirconium oxide is 41%. Products shall be divided into Y(grade one) and H(qualified) two levels according to their physical and chemical indexes, size tolerances and appearance indexes. On the market all kinds of high alumina refractories variety, brand can let the customer the edition, the diversity of products to the customer the opportunity for more options at the same time, also cause some inconvenience to users, as a professional manufacturer of refractory material and CLP investment advice user in the process of choose and buy of vibration let enterprises issued by the relevant certificate and quality system authentication, it is better to field trips, for enterprise strength has a more intuitive understanding.