Glass fiber cloth aluminum silicate refractory fiber classification and temperature
Strictly speaking, the refractory fiber is the high-temperature melt fiberization of aluminum silicate and the fiberization of the normal temperature melt, that is, aluminum silicate oxide fiber and polycrystalline alumina fiber, both of which belong to the category of refractory fibers. .
In a broad sense, refractory fibers belong to amorphous refractory insulation materials, and their fibers can be divided into inorganic fibers and composite fibers. At present, the fibers used as thermal insulation materials on the walls of industrial furnaces are mainly inorganic oxide fibers, and most of them are amorphous fibers of aluminum silicate series, such as ordinary aluminum silicate fibers, high-purity aluminum silicate fibers, high Aluminum fiber, high-purity zirconium-containing fiber and high-purity chromium-containing fiber. A few high-temperature industrial kilns use the principle of polycrystalline mullite fiber and gradient descent, and use refractory fibers with different operating temperatures to form a composite structure lining. In industrial furnaces with furnace temperature greater than 1250C, especially in steel rolling heating furnaces, amorphous refractory fibers are basically mostly used for the insulation layer of furnace walls, and are not allowed to be used on working surfaces. Crystalline fibers, especially polycrystalline mullite fibers, have adapted to the temperature requirements of the steel rolling heating furnace. In my country's steel industry, the pasting of polycrystalline mullite fibers in the steel rolling heating furnace wall has been successful in the 1980s, and has achieved considerable success. energy saving effect.
Amorphous refractory fiber is also called glassy refractory fiber. It has a temperature difference of 200~300 from crystalline fiber. The difference between the two is that the content of Al203 is different. The Al2O3 content of glassy refractory fibers is 45% to 58%, while that of crystalline fibers is 72% to 95%. Glass fibers and crystalline fibers belong to Al2O3-SiO2 series refractory fibers, and the production processes of the two kinds of refractory fibers are different. The production process of glassy refractory fiber is called high temperature melt blowing method or spinning method, and the production process of crystalline refractory fiber is called colloid method or chemical method. The refractory fibers produced by this production process are also known as alumina polycrystalline fibers. When the heat treatment process is changed, continuous fibers or continuous ceramic fibers can also be obtained, and continuous ceramic fibers are added to the ceramic material to achieve the toughening effect of the ceramic material.