Effects of Pore Size Distribution and Composition on Slag Resistance of Porous Spinel

摘要

Corrosion of the porous spinels were conducted using two different grades of sintered spinel with fine pores and homogenous pore distribution containing 62 wt% and 82 wt% Al_2O_3 respectively by SEM, XRD, EDS etc. It was found that pore radius, pore size distribution and composition play very important role in slag resistance. Small pore size and homogeneous pore size distribution are advantageous to improving the corrosion and penetration resistance. Slag penetrates evenly into the spinel with even pore size, while it penetrates unevenly into the spinel with uneven pore size. Because MgO-rich porous spinel has a big average pore size of 16.01 μm and (Mg, Fe, Mn) O is evenly formed in surface of specimen, S-62 has high slag corrosion resistance but low slag penetration resistance. Contrarily, Al_2O_3-rich porous spinel has a small average pore size of 5.43μm, and MgO · (Al,Fe)_2O_3 and materials mainly containing MA and CaO-Al_2O_3 phases are formed alternately in surface of specimen, thus S-82 has high slag penetration resistance but low slag corrosion resistance.