The effects of additives on the properties and structure of hot-pressed aluminium titanate ceramics

The effects of additives (MgO-Al2O3-SiO2, Al2O3-SiO2, Si3N4, SiC) on the properties and structure of hot-pressed aluminium titanate ceramics were studied. The hot pressed samples were characterised in terms of bulk density and apparent porosity by the Archimedes method. Bending strengths and thermal expansion coefficients were determined. In addition, the crystalline phases and microstructure were investigated using XRD and SEM. The results showed that the bending strength of aluminium titanate ceramics with additives was improved greatly, while the thermal expansion coefficient was also increased due to a change of structure. XRD showed that a solid state reaction occurred between the additives and aluminium titanate, and a solid solution was formed. 6 refs.