The following requirements are put forward for the furnace wall lining refractory materials:
1. Sufficient refractoriness
Its refractoriness should be 1650~1780℃, and its softening temperature should be higher than 1650℃.
2. Good thermal stability
The temperature of the furnace wall lining is always constantly changing, and the furnace wall lining often cracks due to uneven heating, which reduces the service life of the furnace wall lining. Therefore, as a refractory for electric furnaces, it should have excellent thermal stability.
3. Good chemical stability
The chemical stability of the material is closely related to the life of the furnace wall lining. The lining material of the furnace wall should not be hydrolyzed and differentiated at low temperature, and should not be easily decomposed and reduced at high temperature. It should not be easy to form low-melting substances with slag during the smelting process, and it should not chemically react with metal solutions and additives, and will not pollute metal solutions. .
4. Small thermal expansion coefficient
The volume should be relatively stable with temperature changes, without sharp expansion and contraction.
5. Has high mechanical properties
It must be able to withstand the discharge of the charge in the low temperature state; when the metal is in a high temperature molten state, it should be able to withstand the static pressure of the molten metal and the strong electromagnetic stirring effect; wear resistance and corrosion resistance under the long-term erosion of the molten metal .
6. Good insulation performance
The lining of the furnace wall must not conduct electricity at high temperatures, otherwise it will cause leakage and momentary circuits, causing serious accidents.
7. The construction performance of the material is good, easy to repair, that is, the sintering performance is better, and the furnace building and maintenance are convenient.
8. Abundant resources and low price.