Microstructure control is a critical issue facing manufacturers of advanced ceramics. Secondary phases, introduced to improve sintering, have become increasingly important in controlling the average grain size and grain-size distribution of the major phase. The effect of ZrO 2 addition (1, 5, 10 % by weight) on tialite type, binary TiO 2 -Al 2 O 3 compositions were investigated at 1550 o C. The influence of CeO 2 , MgO and Nd 2 O 3 on the thermal shock resistance, mechanical strengths, open porosity, bulk density, and microstructure have been studied. Dilatometric analysis, Fourier Transform -Infrared analysis (FTIR), X-Ray Diffraction (XRD) analyses and Scanning Electron Microscopy (SEM) used to study both phase transformation and sintering processes. The addition of ZrO 2 improves the thermal shock resistance of tialite compositions (> 40 reversals of heating at 900 o C followed by rapid cooling in water).