Thermal and mechanical properties of aluminumtitanate-mullite composites (part 1)

Abstract

The thermal expansion, thermal stability and bending strength of aluminumtitanate (AT)-mullite composites prepared from synthesized AT, Newzealand kaolin and aluminum hydroxide were investigated. The results obtained are summarized as follows; (1) The average linear thermal expansion coefficient from 100° to 1100°C increased slightly with increasing amount of AT up to 50wt%, and decreased with further increase in the amount of AT, approaching to be value of fired AT. The average linear thermal expansion coefficients from 1100° to 1400°C in heating and from 1400°C to the turning point in the cooling stage increased monotonously with increasing AT content. (2) The degree of thermal expansion hysteresis decreased with decreasing amount of AT. (3) The bending strength of the composites containing 10-30wt% AT was the highest, and decreased with further increase in the amount of AT. (4) The decomposition of AT in the composites was restrained almost completely.