Advantages of Magnesia Carbon Bricks for Converters
Advantages of magnesia carbon bricks for converters
Magnesium materials have high fire resistance and are alkaline. When magnesia and graphite are combined to form magnesia carbon bricks, magnesia carbon bricks exhibit excellent slag resistance, erosion resistance, impermeability and thermal shock resistance. The main reasons are:
1. Magnesia carbon brick is mainly composed of graphite and magnesia powder. The graphite and magnesia are surrounded by a strong carbon conjugate, which is not easy to slip. C and MgO have no co-solubilization relationship and do not produce liquid phase. During the process of use, the iron oxide in the slag can be reduced to metallic iron after encountering carbon. Due to the reduction, the melting point and viscosity of the slag increase, and the penetration force is greatly reduced.
2. The non-wetting property of slag and molten iron and graphite in magnesia carbon brick. Since the contact angle between the slag and the molten iron and graphite is both 90° or more, the prepared magnesia carbon brick has excellent slag resistance.
3. The protective effect of the dense periclase layer can be formed in the magnesia carbon brick refractory material, thereby preventing the penetration of the slag.
4. The carbon in the magnesia carbon brick reacts with the infiltrated slag to form CO gas. Under the influence of the pressure of the CO gas, the pressure in the pore passage can reach 0.2 MPa (2 atm) or more, which can prevent or delay the infiltration of the slag into the pores.