Magnesium Aluminum Spinel Castable for Electric Furnace
November 30, 2018
Magnesium aluminum spinel castable for electric furnace
The properties of magnesium aluminum spinel refractory castables for electric furnaces are as follows:
1. Volume stability
Magnesium aluminum spinel castable at 1600 ° C, the permanent line change rate after burning for 5 h is between -1.0% and +1.5%. Under the high temperature operation of the electric furnace at 2050 ° C, the liquid phase does not appear, and the electric furnace is in use. In the process, the bottom of the furnace is cracked and peeled off. The thermal expansion rate of the magnesium-aluminum spinel castable can reach 2.45%, which can prevent the over-sintering phenomenon.
2. Good sinterability
Magnesium aluminum spinel castables are used in the hearth of electric furnaces. At the same time as MgO and MgO·Al2O3 as the main materials, MgO ultrafine powder and Al2O3 ultrafine powder are introduced respectively, so that the material has started to work well in the middle temperature stage. The sintering can be as strong as the standard used.
3. High temperature resistance
Magnesium aluminum spinel refractory castables are made of special high-alumina bauxite, high quality synthetic spinel, additives, binders, etc. The castables with MgO and MgO·Al2O3 as the main materials have good high temperature resistance. Long life, safe and stable, it is the ideal material for electric furnace bottom.
In the process of alkaline electric furnace smelting, the initial formation of alkaline oxidizing slag, which contains excess CaO and a large amount of FeO, the initial slag contact the bottom of the furnace is very small, can only contact the erosion to the slope, later formed The alkali reducing slag has a low FeO content, and can contact the eroded bottom during the final slag tapping process. At 1600 ° C, the liquid phase region of the magnesium aluminate spinel castable is small, indicating high resistance to erosion by the electric furnace.