Study of Porosity in Corroded Refractories

In this work, computer image analysis was used in order to characterize the complex porosity found in ceramic refractory materials. The porosities of SiC and Al₂O₃ refractory bricks before and after slagging tests have been examined by both mercury porosimetry and image analysis techniques; the results obtained by these two methods were compared and their differences discussed. Mercury porosimetry underestimated the volume fraction of pores larger than 100 μm, which contributed significantly to the total pore volume of analyzed materials. In contrast, image analysis did not reveal finer porosity, the contribution of which was, however, less important, Image analysis appeared to have the advantage of quantification of local heterogeneities of porosity, and the capabilities of this technique to quantify the variations in the volume of pores adjacent to reaction zones are documented and supported by microscopic observations.