High alumina refractory bricks are also called high alumina fire bricks, or high alumina bricks. Generally refers to refractory bricks with high alumina content. Therefore, sillimanite bricks can also be called high alumina bricks. From the perspective of aluminum content, mullite bricks can also be called high alumina bricks. What is the alumina content of high alumina refractory bricks? The aluminum content mentioned here refers to the content of alumina.
What is the Alumina Content of High Alumina refractory bricks?
High alumina bricks usually refer to refractory bricks with Al2O3 content greater than 48%, which become corundum, mullite, and glass phases during firing. The type and quality of high alumina refractory bricks are different, depending on the aluminum content and the ratio of Al2O3/SiO2, as well as the type and quantity of impurities. Generally, high alumina bricks are classified according to the Al2O3 content.
Common high alumina fire bricks include 48 high alumina bricks, Al2O3≥48%; 55 high alumina bricks, Al2O3≥55%; 65 high alumina bricks, Al2O3≥65%; 75 high alumina bricks, Al2O3≥75%.
For other high alumina refractory bricks, such as mullite refractory bricks, the Al2O3 content is between 65% and 75%, and the main crystal phase is mullite. Corundum refractory bricks, refractory bricks with Al2O3≥90%, the main crystal phase is corundum. Alumina hollow ball bricks, Al2O3≥99% refractory bricks.
From the perspective of the aluminum content of alumina refractory bricks, if you want to know more about high alumina fire bricks, you need to pass indicators such as aluminum content, bulk density, compressive strength, and flexural strength. Refractory brick manufacturers usually judge whether this kind of refractory brick can be used in high-temperature industrial furnaces.
How much do you know about the indicators of high alumina fire bricks?
High-alumina refractory standard fire bricks are aluminum silicate refractory products with a content of aluminum oxide (Al2O3) higher than 48%. If the Al2O3 content is higher than 90%, it is called corundum brick. Due to different resources, national standards are not completely consistent. For example, European countries stipulate that the lower limit of Al2O3 content for high-alumina refractory materials is 42%. In China, according to the content of Al2O3 in high alumina bricks, it is usually divided into three grades. Class I——Al2O3 content > 75%; Class II——Al2O3 content is 60-75%; Class III——Al2O3 content is 48-60%.
High alumina refractory fire brick is a neutral refractory material with an alumina content of more than 48%. It is formed and calcined from bauxite or other raw materials with high alumina content. High thermal stability, and refractoriness above 1770°C. Good slag resistance. High alumina refractory standard fire bricks are used for the lining of steelmaking electric furnaces, glass melting furnaces, cement rotary furnaces, etc.
Application Range of High Alumina Refractory Standard Fire Brick
High alumina refractory bricks are divided into physical and chemical indicators (national standards): LZ-75, LZ-65, LZ-55, and LZ-48 (refractory temperature 1750°C-1790°C). Mainly used in coke ovens, blast furnaces, hot blast stoves, steel ladles, casting systems, boilers, cement kilns, glass kilns, and various kiln linings and thermal equipment. Widely used in metallurgy, the chemical industry, ceramics, casting, machinery, electric power, building materials, petroleum, and other industries.
High Alumina Refractory Bricks Manufacturer
People who understand refractory materials will directly provide refractory material manufacturers with the required aluminum content when purchasing high-alumina bricks. At the same time, the manufacturer of high alumina refractory bricks will be informed of its specific use parts. Such as 48-high alumina bricks and 55-high alumina bricks. Refractory brick manufacturers use this to judge which high-alumina bricks customers need. The national industry standard for refractory materials stipulates the physical and chemical indicators of high-alumina bricks with ordinary aluminum content between 48% and 80%. If the customer needs to purchase 55 high-alumina bricks, and the customer has no other special needs, the refractory brick manufacturer will provide high-alumina refractory bricks according to the requirements of national standards. If it is not a national standard high-alumina brick, the customer needs to provide more indicators such as the aluminum content of the high-alumina brick, and the refractory brick manufacturer adjusts the production formula index of the refractory brick according to its specific requirements. The high alumina refractory bricks received by the end customers are based on the premise that they can meet their production needs.