Possessing with the excellent corrosion resistance and high thermal conductivity which can lead to easily form a protective layer for blast furnace hearth, refractory brick carbon bricks have been used as refractory material for hearths for more than half century.

To further improve its performance, the refractory experts have carried out many investigations recently. Finally, they find out some main reasons which caused the damage. They are including as below:
1) The penetration of molten iron into pores.
2) Erosion due to direct contact with molten iron (dis-solution by carburizing).
3) Embrittlement of the material on hot side (loss of cooling capacity).

In order to enhance its corrosion resistance, the experts have developed new technology to get new magnesia carbon brick through numerous experiments.
1) Add the aluminum oxide which has a good resistance to molten steel.
2) Reduce the pore diameter to prevent the penetration of molten steel and other impurity items.
3) Enhance the high thermal conductivity to reduce the surface temperature.
4) Add the TiC to improve the corrosion against molten steel, increase its viscosity and slow down the flow which could effectively reduce the damage on the MgO-C bricks.

Article sources:

http://www.yilongrefractory.com/news/Technical%20Innovation%20of%20Carbon%20Brick%20for%20Blast%20Furnace%20Hearths.html