Character evaluation of aluminum titanate-mullite composite with low thermal expansion and high strength using AE technique at high temperature

Abstract

Aluminum titanate (TA) ceramics has low thermal expansion with micro crack due to thermal expansion anisotropy, and so it has low strength. In this study, we made aluminum titanate-mullite composites with different composition. In order to evaluate the characteristic change with composition, we investigated the detailed characteristic using AE count and original waveform time-frequency analysis. The composite of higher rate of TA showed higher AE count peak temperature and since it was small in the difference with standard temperature, it was low in the strength. This was good agreement with the result of three points bending.