What is magnesia refractory material? About the composition and characteristics of magnesia refractories
Magnesia refractory is a refractory with magnesite, seawater magnesia and dolomite as raw materials, periclase as the main crystal phase, and a magnesium oxide content of more than 80%. Belongs to alkaline refractory materials.
Magnesia refractories can be divided into two categories: metallurgical magnesia and magnesia products. According to chemical composition and use, it can be divided into metallurgical magnesia, magnesia brick, magnesia silica brick, magnesia alumina brick, magnesia calcium brick, magnesia carbon brick and other varieties. Its performance is greatly affected by the ratio of CaO/SiO2 and impurities. The load softening point and thermal shock resistance of high-purity magnesia bricks are far better than those of general magnesia bricks. It has high refractoriness and good resistance to alkaline slag and iron slag. It is an important high-grade refractory material. Magnesium products are mostly produced by the sintering method, and the sintering temperature is generally between 1500 and 1800°C. In addition, chemical bonding agents can also be added to make unburned bricks and unshaped refractory materials. Mainly used in open hearth furnace, electric furnace, oxidation converter, non-ferrous metal smelting furnace, cement kiln and calcining kiln for alkaline refractory materials, etc.
Lightweight magnesia refractories are widely used in chemical, petroleum, metallurgy, silicate, machinery manufacturing, power and other industrial fields. Magnesium refractories have become one of the widely used auxiliary materials in the metallurgical industry due to their high fire resistance, high high temperature strength and resistance to alkaline slag erosion. For example, the steelmaking process mainly relies on molten slag to remove harmful impurities (the main components of molten slag are CaO, FeO, etc. or are highly alkaline CaO–slag system). To resist the corrosion of these slags and absorb harmful impurities in steel, and to make clean steel, only alkaline magnesia refractories are the most suitable; low-viscosity slag (silicon oxide, iron oxide) is produced during the fire smelting of non-ferrous metals , Non-ferrous metals, sulfides, etc.), to resist the erosion of these slags, it is also inseparable from magnesia refractories. The main factor affecting the performance of magnesia refractories is its chemical composition.