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Al₂TiO₅ based ceramics with high mechanical strength and good thermal shock resistance were successfully prepared by adding 1 % -7 % CaO to the alumina titanium dioxide mixtures at 1280-1380 °C for 0.5 h, and the effects of the CaO additive and firing temperature on the phase composition and thermo-mechanical properties of the Al₂TiO₅ ceramics were investigated in the present work. The results show that CaO could promote the formation of the Al₂TiO₅ solid solution, showed a significant impact on the development of the phase composition. The aluminium titanate ceramics sintered with 3% CaO at 1350 °C for 30 min gave an average thermal expansion coefficient of (20-600 °C) 0.83×10-6 K-1, and a bending strength before and after three thermal shock cycles in water from 600 °C to room temperature of 40.59 MPa and 42.23 MPa, respectively.

Aluminium titanate (Al₂TiO₅) based ceramic materials were successfully processed through the addition of porcelain clay and different amounts of CaO to the stoichiometric alumina - titania mixtures that contain commonly used MgO and Fe₂O₃ additives at 1350-1400 ̊C for 1 h. The effect of the addition of CaO and sintering temperatures on the formation of the Al₂TiO₅ ceramics and thermal-mechanical performances were investigated. The results revealed that CaO promoted the formation of a long columnar Al₂TiO₅ solid solution and anorthite as well as gahnite phases. Due to the mismatch of the thermal expansion coefficient between the Al₂TiO₅ solid solution crystals and the anorthite and gahnite phases, a compressive residual stress developed on the surface of the Al₂TiO₅ solid solution particulates, effectively improving the mechanical properties and inhibiting the thermal decomposition of the Al₂TiO₅ solid solution and the microcrack propagation. The average thermal expansion coefficient (20-800 ̊C) of the sample with 3 wt% CaO sintered at 1400 ̊C for 60 min was 0.80×10-6 ̊C-1, and the flexural strength of the sample with 5 wt% CaO sintered at 1380 ̊C was as high as 58.59 MPa, with a 12.43 % increase in the strength after the thermal shock test.