In the process of using the intermediate frequency furnace, the thickness of the refractory material used in the furnace lining is only 70-110mm, the inside of the intermediate frequency furnace lining is in contact with the high temperature liquid metal, the outside is close to the water-cooled coil, the temperature difference between the inside and the outside of the refractory is very large, and it is in the relatively thin section and the strong corrosive environment of many melting operations. The main process conditions affecting the lining damage include melting temperature, degassing time, primary degassing volume, chemical composition of slag and steel type produced. The main factors affecting the destruction of lining are: chemical corrosion of slag, spalling of refractory structure and thermal corrosion.
1.Induction furnace lining refractory material and the characteristic:
Induction furnace lining is usually made of refractory materials composed of various sizes and sizes (commonly used refractory materials are mainly magnesium, quartz, aluminum and composite materials four categories).
Characteristics: direct combination. Therefore, the corrosion resistance is high, the mechanical strength is high, and the thermal shock resistance is good.
2. Damage mechanism of magnesia lining material
Taking magnesia refractories as an example, the damage mechanism of magnesia refractories is described:
The main manifestations of magnesium material damage are: thermal erosion caused by liquid steel flow and chemical erosion caused by slag components penetrating into the material.
In the smelting process, the solution will enter the refractory matrix through the capillary channels into the refractory matrix and corrodes the lining. Components entering the interior of the refractory matrix include; CaO, SiO2, FeO in slag; The Fe, Si, Ai, Mn, C in the liquid steel, even contains metal vapor, CO gas and so on. These entry components are deposited in the capillary channels of refractory materials, forming a discontinuity between the physical and chemical properties of the refractory working surface and the original refractory matrix, and will show cracks, falling off and loose structure under the sudden change of operating temperature. In a severe way, this damage process is much more severe than the dissolution damage process.