In order to improve the poor oxidation resistance, corrosion resistance and permeability of ordinary carbon bricks, microporous carbon bricks with an average pore size of less than 0.5um were developed. Microporous carbon brick is a refractory made of anthracite calcined at 1500-2000 ℃ as the main raw material, a small amount of graphite powder and silicon powder, and medium temperature asphalt as the binder.
The formation of micro pores in microporous carbon brick is due to the addition of metal silicon in carbon brick. Silicon particles melt and gasify at a certain temperature, penetrate and diffuse into the cracks and voids of carbon brick, and form redistribution. Gaseous Si reacts with C at a certain temperature β- SiC, this β- SiC fills almost all the cracks and pores in the carbon brick and deposits on the pore wall, which is formed by reaction β- SiC can fill pores, reduce pore size and reduce air permeability.
Microporous carbon brick not only has excellent conventional properties, but also has good alkaline resistance, thermal conductivity, molten iron corrosion resistance, oxidation resistance and molten iron permeability. Microporous carbon bricks are mainly used in the erosion area of blast furnace and other weak parts of high aluminum.
