Refractory materials are non-metallic materials with a refractoriness not less than 1580°C, good resistance to thermal shock and chemical attack, low thermal conductivity and low expansion coefficient. Refractory materials are widely used in metallurgy, chemical industry, petroleum, machinery manufacturing, silicate, power and other industrial fields, and are used the most in the metallurgical industry, accounting for 50% to 60% of the total output.
Great Varieties:
There are many types of refractory materials, usually divided into ordinary refractories (1580~1770℃), advanced refractories (1770~2000℃) and special grade refractories (above 2000℃) according to their refractoriness; according to their chemical characteristics, they are divided into acidic refractories, Neutral refractories and alkaline refractories. In addition, there are refractory materials for special occasions. Anyang Jinrong`s products are advanced refractories, Tundish Nozzle Material and Refractories For Steel Ladle are best used in continuous casting.
Ingredient content:
Acidic refractories are mainly composed of silica, and commonly used are silica bricks and clay bricks. Silica brick is a siliceous product containing more than 94% silicon oxide. The raw materials used are silica, waste silica bricks, etc., with strong resistance to acid slag erosion, high load softening temperature, and no shrinkage or even slight expansion after repeated calcination; However, it is easily corroded by alkaline slag and has poor thermal shock resistance. Silica bricks are mainly used in thermal equipment such as coke ovens, glass melting furnaces, and acid steel furnaces. Clay bricks use refractory clay as the main raw material and contain 30% to 46% alumina. They are weakly acidic refractory materials with good thermal vibration resistance and corrosion resistance to acidic slag, and are widely used.
Neutral refractories are mainly composed of alumina, chromium oxide or carbon. The corundum product containing more than 95% alumina is a high-quality refractory material with a wide range of uses. Chrome bricks with chromium oxide as the main component have good corrosion resistance to steel slag, but have poor thermal shock resistance and low deformation temperature under high temperature load. Carbon refractory materials include carbon bricks, graphite products and silicon carbide products, which have low thermal expansion coefficient, high thermal conductivity, good thermal shock resistance, high temperature strength, resistance to acid, alkali and salt corrosion, especially weak acids and alkalis. Good resistance, not wetted by metal and slag, light weight. It is widely used as a high-temperature furnace lining material, and also as an autoclave lining for petroleum and chemical industries.
Alkaline refractories are mainly composed of magnesium oxide and calcium oxide, and magnesia bricks are commonly used. Magnesium bricks containing more than 80%-85% of magnesium oxide have good resistance to alkaline slag and iron slag, and have higher refractoriness than clay bricks and silica bricks. Mainly used in open hearth furnace, oxygen blowing converter, electric furnace, non-ferrous metal smelting equipment and some high temperature equipment.
Refractory materials used in special occasions include high temperature oxide materials, such as aluminum oxide, lanthanum oxide, beryllium oxide, calcium oxide, zirconium oxide, etc., refractory compound materials, such as carbides, nitrides, borides, silicides and sulfides Etc.; high-temperature composite materials, mainly cermets, high-temperature inorganic coatings and fiber-reinforced ceramics.
Common refractory materials:
Frequently used refractories include AZS bricks, corundum bricks, direct-bonded magnesia-chrome bricks, silicon carbide bricks, silicon nitride bonded silicon carbide bricks, nitrides, silicides, sulfides, borides, carbides and other non-oxide refractories ; Refractory materials such as calcium oxide, chromium oxide, aluminum oxide, magnesium oxide, and beryllium oxide.
Frequently used heat-insulating refractory materials include diatomite products, asbestos products, insulation boards, etc.
Frequently used unshaped refractory materials include repair charge, refractory ramming material, refractory castable, refractory plastic, refractory mud, refractory gunning material, refractory projection material, refractory coating, lightweight refractory castable, gun mud, etc.
