SYNTHESIS OF ALUMINUM TITANATE-MULLITE COMPOSITE HAVING HIGH THERMAL-SHOCK RESISTANCE

Improvement of mechanical properties through better processing is expected for materials having a high thermal expansion anisotropy such as aluminium titanate and mullite. In this study, processing using hydrolysis of alcohoxide was applied to develop a better composite. The compositions containing 22, 63 and 91 vol% aluminium titante were selected for examination because high strength, moderate strength and thermal shock resistance, and high thermal shock resistance, respectively, were expected. With increasing aluminium titanate content, the room temperature strength and relative density decreased. Young's modulus and thermal expansion coefficient were maximum at an aluminium titanate content of 63 vol%. The high thermal shock resistance of the composite having 91 vol% aluminium titanate can be attributed to the presence of microcracks. This conclusion was reached from the low Young's modulus, low strength and low thermal expansion coefficient which are characteristic only for this composite.