Physical and thermal characteristics of aluminium titanate dispersed with β-spodumene and zirconia

The effects of β-spodumene (Li₂O·Al₂O₃·4SiO₂) and zirconia additives on the physical and thermal characteristics aluminium titanate (AT) ceramics have been investigated. XRD, DTA, SEM, TEM and dilatometry have been used to characterise the influence of these additives on phase relations, densification, microstructure, thermal expansion, thermal decomposition and thermal shock behaviour of AT. The results show that the presence of both β-spodumene and zirconia significantly reduces porosity, lowers thermal expansion, improves densification, hardness and thermal stability, without degradation of thermal shock resistance. Microstructural examinations have revealed the presence of glassy phase due to the phase separation of β-spodumene and spontaneous microcracks due to thermal expansion anisotropy of AT.