Effects of CaCO3 additive on the phase, physical, mechanical, and microstructural properties of zirconia-toughened alumina-CeO2-Nb2O5 ceramics

This work studied the effects of CaCO3 additive on the phase, physical, mechanical, and microstructural properties of zirconia-toughened alumina-CeO2-Nb2O5 ceramics prepared via wet milling. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were utilised to analyse the role of secondary phases, particularly hibonite, and their impact on the phase, physical, mechanical, and microstructural properties of this type of ceramic. EDX analysis showed that the hibonite phase contributed to elongated grains among the secondary phases. Vickers indentations indicated a significant difference in the compositional adjustment efficiency among the composites. Excellent Vickers hardness and fracture toughness for 1.0 wt% CaCO3 added resulted in 7.9% hibonite at 1,422.46 HV and 5.84 MPa root m, respectively.