Aluminum carbonaceous special refractory material refers to carbon composites which use alumina and carbon as raw materials. In most cases, other raw materials are also added, such as SiC, metal Si, Al, etc., bonded with organic binders such as asphalt or resin. Special refractories. Broadly speaking, refractories with alumina and carbon as the main components are called aluminum-carbon refractories. Aluminium carbonaceous refractory materials can be divided into two categories according to their production processes: non-fired aluminum carbonaceous refractory materials and fired aluminum carbonaceous refractory materials.

Non-fired aluminum carbonaceous refractory material is a carbon-bonded refractory material. Because of its significantly better oxidation resistance than magnesia-carbon bricks, and excellent corrosion resistance against Na2O slag, it is widely used in hot metal pretreatment equipment such as blast furnaces and ladle. Applications. The fired aluminum carbonaceous refractory material is a ceramic-bonded refractory material. Because of its high strength, good resistance to erosion and thermal shock, a large number of skateboard tiles and three continuous casting pieces are suitable for sliding nozzle systems for continuous casting. Long nozzle, immersion nozzle and integral stopper.

Rhenium alumina has high resistance to acid, alkaline slag, metal and glass solutions. It can be used in an oxidizing atmosphere or a reducing atmosphere at a high temperature, and can be used well. Carbon raw materials, especially graphite, have high thermal conductivity and low coefficient of linear expansion, and are non-wetting with slag and high-temperature solutions. Therefore, aluminum carbon brick has the following properties.

(1) Aluminum carbon refractory has excellent slag resistance and thermal shock resistance. Compared with magnesium carbon refractory, aluminum carbon refractory has better resistance to alkali erosion and TiO2 slag erosion.

(2) For fired aluminum-carbon bricks, since the additive silicon and carbon react at high temperature to form silicon carbide, which has a dual bonding system, that is, carbon bonding and ceramic bonding, the fired aluminum carbonaceous refractory has high mechanics. Performance, not only acts as a traditional refractory, but also a functional structural material in continuous casting.

At present, aluminum-carbon refractory mainly uses fused corundum, sintered corundum or sintered plate-shaped corundum, special grade or grade Ⅰ high-quality alumina clinker as the coarse particle component of the product. Corundum fine powder or fused mullite, sintered synthetic mullite fine powder, or synthetic high mullite fine powder can also be used. Adding a certain amount of carbon to the product is beneficial to improving the properties of the product and extending the service life. Carbon has a high melting point, a small linear expansion coefficient, and good thermal conductivity. Carbon can penetrate into the pores of the particles in the product or form a vein-like network carbon chain structure between the particles, forming a "carbon bond", thereby reducing the porosity of the product and increasing the high temperature strength of the product. Carbon can also form a surface that is not corroded by metals and slag, improving the corrosion resistance and thermal shock resistance of the product. In addition, the presence of carbon creates conditions for the reduction of iron and silicon oxides, and the resulting metal does not react chemically with the refractory material. During the reduction of the oxide by carbon, the generated gas can prevent the Rongrong oxide from penetrating into the refractory. Carbon can also improve the thermal conductivity of the product to avoid exfoliation and fracture of the brick due to uneven temperature overheating in individual parts of the product. Therefore, the carbon raw materials in aluminum carbon bricks are mainly flaky natural graphite, pyrolytic high-purity graphite can also be used, and carbon black is usually added. Antioxidants are metal Al, Si powder and SiC, B4C powder. Adding a small amount of antioxidant can delay the oxidation of the carbon-containing layer and increase the service life of the product.