Synthesis and structural characterization of Al ₂ TiO ₅ –mullite composite

Al 2 TiO 5 –mullite material was produced through the sintering process using Algerian natural raw materials. The selected raw materials included kaolin KT (45 wt.%), potassic feldspar (30 wt.%), and quartz (25 wt.%), with TiO 2 nanoparticles added at concentrations of 5 and 10 wt.%. The mixture was milled for 8 h at room temperature in a high-energy planetary ball mill under an argon atmosphere. After milling, the powders were pressed into pellets and then sintered for 2 h at a temperature of 1,200 °C in air. The effect of TiO 2 nanoparticle addition on the physical and structural properties of the porcelain was analyzed using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, as well as bulk density and shrinkage measurements. The sintered ceramics primarily showed mullite and quartz. With 5 wt.% TiO 2 , aluminate titanate (Al 2 TiO 5 ) began to form in addition to the existing phases, while rutile was observed as an unreacted phase. Increasing TiO 2 content to 10 wt.% led to a higher volume fraction of Al 2 TiO 5 and a reduction in mullite content. The overall densification of the ceramics improved with the addition of TiO 2 , enhancing physical and microstructural properties.