Magnesia refractory brick refers to a kind of refractory brick with magnesia as the raw material, periclase as the main crystalline phase and MgO content of 80% -85%. Its products are divided into two major categories of metallurgical magnesia and magnesia products. Depending on the difference of chemical composition and use, there are Martin Sand, ordinary metallurgy magnesia, ordinary magnesia, magnesia-silica brick, magnesia-alumina brick, magnesia-calcium brick, magnesia-carbon brick and other varieties. Magnesia refractory bricks is the most important alkaline refractory products, high refractoriness, good resistance to alkaline slag and iron slag, is an important advanced refractory bricks. Mainly used in open hearth, oxygen converter, electric furnace and non-ferrous metal smelting.