Abstract: By means of various processes, thermodynamic calculation, XRD, SEM, thermal expansion coefficient and bending strength, the effects of sintering temperature, pressing methods, sintering process and atomsphere on the properties of AT ceramics were studied. The experimental results show that the comprehensive properties of the ceramics between thermal expansion coefficient and bending strength are improved by isostatic pressing, hot pressing and silicon. Moreover, the change of mechanical properties of AT and AT with 10%A 3S 2 ceramics at high temperature and after thermal shock is explained in comparision with their thermal expansion curves, respectively.