Microstructure, Mechanical and Thermal Properties of ZTA/Al2TiO5 Ceramic Composites

Zirconia-toughened alumina (ZTA)/Al2TiO5 composites were prepared via a sol-gel route. The prepared samples were uniaxially pressed and pressurelessly sintered at 1650-1700 degrees C for 1 h. The microstructure, densification, and X-ray diffraction patterns of the sintered ZTA/Al2TiO5 composites were investigated, and their mechanical properties, thermal coefficient, and shock resistance were characterized. The addition of Al2TiO5 hindered the grain growth of the alumina particles and enhanced the relative density, Vickers hardness, and bending strength of the composites compared with pure ZTA samples. The fracture toughness was improved by 19% upon the addition of 40 wt% Al2TiO5. Moreover, increasing the Al2TiO5 content resulted in an improvement in the thermal shock resistance.