BEHAVIOR OF Al_4SiC_4 ADDED TO THE CARBON CONTAINING REFRACTORIES

摘要

The behavoir and effect of Al_4SiC_4 powder added to the MgO-C bricks have been investigated and discussed. The conclusions are as follows. (1) The mass increases and the porosity decreases in the MgO-C brick which was added Al_4SiC_4 powder above 1000℃. The apparent porosity after heating at 1500℃ is 2% lower than that after heating at 800℃. (2) The brick strength increases gradually above 1000℃ by the addition of Al_4SiC_4 powder. (3) Al_4SiC_4 powder improves the oxidation resistance of the bricks as well as aluminum powder. The bricks containing Al_4SiC_4 has high slaking resistance after heating. (4) Al_4SiC_4 reacts with CO gas to form spinel(MgAl_2O_4) and SiC above 1200℃. The formed SiC also reacts with CO gas and MgO to form forsterite(Mg_2SiO_4) above 1400℃. ALA and A1N are not formed in these reaction processes. (5) The increase of mass and volume are caused by the reaction of Al_4SiC_4 and CO gas, the more densification of the texture is provided.