Characteristics of Magnesia-calcium Brick
Characteristics of magnesia-calcium brick
Magnesia-calcium brick is composed of MgO and CaO and is an alkaline refractory material. And it has the following characteristics:
1, High temperature resistance
The main components of magnesia-calcium bricks are MgO and CaO, both of which are high melting point (2800 ° C and 2570 ° C) oxides, and the co-melting temperature is also above 2300 ° C, so it has good high temperature resistance.
2, Slag resistance
Magnesia-calcium brick has good slag resistance, and the slag alkalinity increases the slag erosion rate will decrease rapidly. The slag invading the brick reacts with CaO in the brick to form C2S and C3S, which is the slag viscosity becomes higher and the wetting angle increases. Prevent the slag from penetrating into the interior of the brick without forming a colloidal layer. For the low alkalinity slag, the CaO of the magnesia-calcium brick is first dissolved, so that the slag is highly alkaline and highly viscous, so that it is more difficult to dissolve, and the magnesia-calcium granule can improve the slag resistance.
3, Thermal shock resistance
Magnesia-calcium bricks contain more free CaO. At high temperatures, the creep is large, and the plasticity can buffer the heat generated by temperature fluctuations, and has good thermal shock resistance.
4, Purification of liquidity
Magnesia-calcium brick contains more free CaO, which is easy to react with inclusions in molten steel, and migrates into slag, which has the function of removing impurities and purifying molten steel.
5, High temperature stability
The high-purity magnesium dolomite brick is stable under high temperature vacuum and has a small weight loss rate, and is more suitable for use in an off-furnace refining furnace having a high temperature vacuum working environment.
6, Easy to hydration
The CaO in the magnesia-calcium brick reacts as long as it encounters water to form Ca (OH)2, which causes it to swell, and the magnesia-calcium sand is powdered, and the brick is cracked or cracked.