July 18, 2018
The high-aluminum castable is a high-alumina aggregate with an AL2O3 content of more than 75% as a pellet raw material, combined with a high-aluminum powder and an admixture composed of an unshaped refractory castable having an overall aluminum content of More than 75%, after the initial setting of the high-aluminum castable is formed. Standard curing to 28d, pressure strength up to 40~60MPa. It is characterized by slow hydration speed, high strength and high refractoriness in the later stage.
It has high temperature performance, high tolerance, wide temperature, no shrinkage, and wear resistance. High-aluminum castables are widely used in hardware, smelting, chemical, non-ferrous metals and other industries, especially in the steel industry, with a wide temperature range. There is basically no shortening after high temperature, which overcomes the shortcomings of refractory concrete in the past. Goods are easy to store, transport and use. High alumina castables are classified into conventional and low steel and ultra low steel. Nowadays, it is important to use low-steel type on heavy steel, while ultra-low-steel type high-aluminum castable is used in metallurgical furnace of non-ferrous industry.
The amount of cement used in aluminum castables is low, and the amount of calcium in castables is only 1/4-1/3 of that of conventional refractory castables. Therefore, the number of low-melting phases in the low cement castable is reduced, so that the high-temperature performance can be significantly improved; the construction water consumption is low, generally 6%-7% of the weight of the castable, and thus has high density and low porosity. Not only has a high room temperature curing strength, but also does not decrease in strength after medium temperature and high temperature treatment, the absolute value of the strength is 3-5 times that of the conventional refractory castable; it has good volume stability at high temperature, although not The refractory material is fired, but after drying and calcination, the volume shrinkage is small.