Effect of Zirconia (ZrO2) Addition on Some Characteristics of Iraqi Bauxite Refractories


Use Iraqi Bauxite (64.2%) Alumina was calculated at (1400 oC ) and Graingradient limited after add kaolin and Sodium Silicate to increase compaction bauxite grain and then addition different weight percentage from zirconia to mixture (0, 5, 10, 15, 20 %wt). The specimens were formed by using bi- axial pressing. These specimens were fired in two temperatures (1200 oC , 1400 oC) . Studies the physical properties (density and porosity), mechanical properties (Diametrical strength) and thermal shock,. Increasing of zirconia percentage leads todecreasing of porosity, and increasing of (density and Diametrical strength). also, thermal shock effective passively on diametrical strength, where diametrical strength decreasing with increasing shock temperature. Add zirconia effected on properties from two sides; first from side general characteristics and another from side made zirconium silicate phase