What are the requirements for the performance of refractory materials?
Refractory materials should have very high refractoriness, high temperature heat load and resistance to softening, melting; with high volume stability, resistance to high temperature and heat load, volume shrinkage and only uniform expansion; high strength at room temperature and high temperature strength, high load softening temperature, under the joint action of heat load and heavy load, no loss of strength, creep collapse; Electric furnace analysis should have good resistance to thermal shock, resistance to rapid temperature changes, no crack, not flaking; with excellent slag resistance.
Electric furnace bottom and furnace slope and the wield pool should be magnesia whole knotting, magnesia carbon brick and tar magnesia brick; hot and slag line area, using high-quality magnesia-carbon brick; Brick on both sides of the furnance door should be tapping El magnesia brick, magnesite chrome brick; electric furnace cover should be high alumina brick and high alumina bricks.
Performance requirements for electric furnace lining refractory: 1, sufficient refractoriness and softening point. Because of eletric arc, the inner surface temperature of lining can be as high as 1500 to 1800 degree. 2, strong resistance to slag. Because the dust penetrate into the furnace through pore lining, and the refractory material subject to loss, leading to spalling. 3, good thermal and shock resistance. Because during steelmaking, opening door and lifting of the furnace will lead to sudden changes in the temperature of the furnace lining refractory material, so spalling and cracking may occur, damaging the lining premature. 4, enough strength, because the lining is impact during charging, tilted when vibration,and eroded by metal, slag and airflow. 5, the thermal conductivity shall be small, and the conductivity shall be low. The commonly used furnace refractories are dolomite brick, magnesia brick, high alumina brick, silica brick and magnesia ramming etc.. Because of different working conditions of the various parts of the furnace, the refractory materials are not the same.
