Hot pressing of gadolinium zirconate pyrochlore

The results of studies on preparation of gadolinium zirconate pyrochlore ceramics are presented. Gd2Zr2O7 powders were prepared by repeated annealing and milling runs of commercial ZrO2 and Gd2O3 micro- and nanopowders and hot-pressed at 1450 °C. Scanning Electron Microscopy (SEM) analysis of the microstructure shows average grain size to vary from 1.0 to 5.9 µm depending on a type of used mixtures. Sintered ceramics were characterized by X-ray diffraction. The highest intensity of the pyrochlore superstructure peaks was found for ceramics obtained from the mixture of nanopowders. The ratio of intensity of the strongest pyrochlore line to the intensity of the strongest peak characteristic for both structures (fluorite and pyrochlore) equals to 4.5% indicating about 80% pyrochlore ordering.