Effect of La2O3 addition and sintering mode on the mechanical properties and microstructural evolution on an 8YSZ ceramic alloy

Abstract

Abstract In this research, the influence of La2O3 addition on the microstructure, phase stability and mechanical properties of 8\u202fmol% yttria stabilized zirconia (8YSZ) was studied. 8YSZ with La2O3 (9, 12 and 15\u202fwt%) ceramics were fabricated by microwave and conventional sintering at 1400\u202f°C/ 20\u202fmin and 1400\u202f°C/ 5\u202fh, respectively. Irrespective of the sintering technique, the relative sintered density was found to decrease with increasing amount of La2O3. The grain growth of 8YSZ was enhanced significantly by the addition of La2O3. The XRD results demonstrated that addition of La2O3 up to 15\u202fwt% did not disrupt the cubic 8YSZ phase regardless of sintering technique; additionally evolution of pyrochlore phase, La2Zr2O7 was observed in all sintered specimens. Vickers hardness of 8YSZ ceramic compacts were also found to decrease with increasing amount of La2O3.