How is the expansion coefficient of magnesia carbon brick calculated

The object has expansion and contraction due to the change of magnesia carbon brick manufacturer. The change capacity is expressed by the volume change caused by the change of unit temperature under constant pressure (P), that is, the coefficient of thermal expansion α=Δ V/(V* Δ T). (where) Δ V is the given temperature change Δ Change of object volume under t, V is the object volume) magnesia brick manufacturer

In the past 20 years, the output and varieties of China's iron and steel industry have developed greatly. In order to adapt to this development, the varieties and equipment of refractories in China have been continuously updated. More than 10 categories and more than 100 brands have been added to the varieties, which has changed the traditional four categories of varieties structure dominated by clay, high aluminum, siliceous and magnesium products in the past. According to the development focus of the iron and steel industry, although the steel output will not increase greatly, the steel continuous casting ratio and refining ratio will continue to improve, and the equipment will continue to tend to be large-scale and modern. These characteristics of the development of iron and steel industry have prompted refractory materials to continue to improve product quality and expand varieties. At the same time, some refractory materials with specific functions are produced around energy conservation and consumption reduction.

The production process of fired magnesia chrome brick is roughly similar to that of magnesia brick. In order to eliminate the loose effect caused by the expansion of spinel formed by the reaction of MgO with Cr2O3, Al2O3 or iron oxide in the firing process of brick, magnesium chromium brick can also be made of synthetic co sintered material. In addition, there are unburned magnesia chrome bricks, such as unburned magnesia chrome bricks combined with inorganic magnesium salt solution. Unburned magnesia chrome brick has the advantages of simple production process, low cost and good thermal stability, but its high-temperature strength is far less than that of fired brick. In the late 1950s, a so-called "directly combined" magnesia chrome brick was developed. The brick is characterized by pure raw materials, high firing temperature, direct combination between high-temperature phases such as periclase and spinel, and island distribution of low melting phases such as silicate. Therefore, the high-temperature strength and slag resistance of the brick are significantly improved.

The method of making bricks with fine powder made by chrome ore magnesia co grinding and pressing blank calcined and combined with coarse magnesia particles is an effective measure to eliminate the loosening effect. Compared with ordinary magnesia chrome bricks, the magnesia chrome bricks made by this method have lower porosity, higher compressive strength, load softening temperature and flexural strength. The magnesia chrome brick made of chrome magnesite powder compact and synthetic magnesia chrome sand calcined at high temperature has better slag resistance and high temperature strength than other magnesia chrome bricks.