Common and special refractories commonly used varieties

Posted by adela li on October 24th, 2016

The larger the amount of silica brick and clay brick. Silica brick is more than 93% SiO2 silica products, the use of raw materials are silica, waste silica brick. ladle slide gate Silica brick acid-resistant slag erosion ability, but susceptible to alkaline slag erosion, its load softening temperature is high, close to its refractoriness, repeated calcination volume does not shrink, or even a slight expansion, but the anti-refractory abrasive heat Seismic poor. Silica brick is mainly used in coke oven, glass furnace, acid furnace and other thermal equipment. Clay brick containing 30% to 46% alumina, refractory clay as its main raw material, refractoriness 1580 ~ 1770 ℃, good thermal shock resistance, is a weak acid refractory, acidic slag corrosion resistance, wide range of uses, Is the largest production of a class of refractories.
Neutral refractories
High alumina products in the main phase is mullite and magnesia carbon brick corundum, corundum content with the increase in the content of alumina increased, with more than 95% alumina corundum products is a wider use of high-quality refractory. Chrome brick is mainly made of chrome ore as raw material, the main crystal phase is chromite. Its good ladle refractory corrosion resistance of steel slag, but the thermal shock resistance is poor, high temperature load deformation temperature is low. Chromium and magnesia in different proportions made of chrome magnesia brick thermal shock resistance is good, mainly for alkaline flat top brick. Carbon products is another kind of neutral refractory material, which is divided into three categories: carbon brick, graphite product and silicon carbide based on the composition of carbonaceous material and the mineral composition of the product. Carbon brick is a high-grade petroleum coke as raw material, plus tar, asphalt binder, at 1300 ℃ isolated from the firing of air conditions. Graphite products (except natural graphite) with carbonaceous materials in the electric furnace in 2500 ~ 2800 ° C in the graphite system in the system. Silicon carbide products are silicon carbide as raw materials, plus clay, silica and other binder in 1350 ~ 1400 ℃ firing. Silicon carbide plus silicon powder can also be made in the electric furnace nitrogen atmosphere under silicon nitride - silicon carbide products. Refractories abrasive
Carbon products, low thermal expansion coefficient, high thermal conductivity, good thermal shock resistance, high temperature strength. Long-term use at high temperatures do not soften, from any acid-base erosion, a good salt resistance, not by the metal and slag wetting, light, high-quality high-temperature materials. Disadvantage is easily oxidized at high temperatures, should not be used in the oxidizing atmosphere. Carbon products are widely used in high-temperature furnace lining (bottom, hearth, lower furnace, etc.), melting non-ferrous metal furnace lining. Graphite products can do the reaction tank and petrochemical autoclave lining. Silicon carbide and graphite products can also be made of melting copper with gold and light alloy crucible.
Alkaline refractories
To magnesium products as the representative. It contains magnesium oxide 80% to 85% or more to periclase-based crystal phase. Magnesite production of the main raw materials are magnesite, seawater magnesia from the sea water extracted from the high temperature calcination of magnesium hydroxide) and so on. Alkaline slag and iron slag has a good resistance. The melting point of pure magnesium oxide up to 2800 ℃, so the magnesia refractory than clay brick and silica brick are high. Since the mid-1950s, the use of oxygen-oxygen converter steelmaking and the use of alkaline flat furnace top, alkaline refractory production increased gradually, clay brick and silica brick production is reduced. Alkaline refractories are mainly used for open hearth furnace, oxygen blowing converter, electric furnace, non-ferrous metal smelting and some high-temperature thermal equipment.
Oxide material
Such as alumina, lanthanum oxide, beryllium oxide, calcium oxide, zirconium oxide, uranyl oxide, magnesium oxide, cerium oxide and thorium oxide, and the like have melting points in the range of 2050 to 3050C.
Refractory compound material
(Boron nitride, titanium boride, hafnium boride, etc.), silicides (such as disilicide (such as silicon carbide, silicon carbide, silicon carbide, and the like) Molybdenum, etc.) and sulfides (thorium sulfide, cerium sulfide, etc.). Their melting point for the 2000 ~ 3887 ℃, of which the most refractory is the carbide.
High Temperature Composites
Such as metal ceramics, high temperature inorganic coatings and fiber-reinforced ceramics.

Refractory company Henan Xinmi Changxing Refractory Material Co., Ltd. Located in Henan Province,China.ChangXing's product portfolio covers shaped products such as refractory materials,refractory brick, refractory castable,refractory nozzle, ceramic fiber, slide gate, etc; unshaped products including repair, construction and casting mixes and mortars.exported to more than 20 countries, such as Thailand, Indonesia, Pakistan, Saudi Arabia, South Africa, Turkey, Iran, Iraq and so on.