The dependence of properties of alumina-zirconia-graphite refractories on particle size distribution by furnas model

The alumina-zirconia-graphite (AZG) refractories were obtained through baki ng techniques using fused Al2O3, partially stabilized ZrO2 and flake graphi te as the starting materials with Al, Si, and SiC powders as additives. Fur nas model are used to describe the particle size distribution for coarse Al 2O3 (500-1000 mu m)/medium Al2O3 (61-125 mu m)/fine Al2O3 (<44 mu m) in whi ch the contents of coarse, medium and tine Al2O3 powders are variable on th e basis of constancy of other fine particles in the matrix. Bulk density of AZG refractories determined by Furnas model is about 3.0 g/cm(3). The lowe st apparent porosity (5.1%) was obtained at a weight ratio for coarse Al2O3 /medium Al2O3 of 2.14 The reheat linear change fraction is 0.1-0.2% for all samples, indicating that this material has acceptable volume stability. Th e number of air exposure cycles for the thermal shock resistance (R-st) wer e 11-16, and the relation of R-st with apparent porosity (P-o) is correlate d by R-st = 1.12P(o) + 5.91. The relation of erosion fraction (E-r) with P- o is expressed as E-r = 0.30P(o) - 0.27. Therefore, the R-st increased and the E-r decreased while the P-o increased in this AZG system.