Aluminium Titanate-Aluminia Composites Synthesized by Heterogeneous Precipitation Method

Aluminium titanate-alumina (AT-A) composites were sintered from the precursor powders prepared by two different methods: a simple sol-gel based heterogeneous precipitation method and a traditional blending method. The crystalline phase, microstructure, mechanical strength, sintering properties, and thermal expansion coefficient (TEC) of the sintered AT-A composites were investigated and compared. The heterogeneous precipitation method increases the homogeneity of the precursor powders and improves the mechanical and sintering properties of the AT-A composites. The AT-A composites with a Al:Ti ratio of 2.2 achieve the optimal performance where the bending strength is high and the TEC remains low.