L1(2)- and L1(0)-like cation-ordered structures in ZrO2-Y2O3 ceramics

Y0.25Zr0.75O2-x and Y0.5Zr0.5O2-y phases, with L1(2-) and L1(0-) like cation-ordered structures, respectively, have been found in ZrO2-Y2O3 ceramics in both the sintered and annealed states. High-resolution electron microscopy, energy-dispersive x-ray spectroscopy and computer simulation have been used to reveal the presence of the phases. The formation of Y0.25Zr0.75O2-x, and Y0.5Zr0.5O2-y phases was initiated during the sintering procedure and developed with the increase in annealing temperature and time. Segregation of yttrium, which was prevalent in different regions even within one grain, induced the formation of Y0.25Zr0.75O2-x and Y0.5Zr0.5O2-y phases.