Nanodomains of pyrochlore formed by Ti ion implantation in yttria-stabilized zirconia

The microstructural evolution of a single crystal of yttria-stabilized zirconia (YSZ) implanted with Ti has been studied by cross-sectional transmission electron microscopy (TEM). The implantation of 180 keV Ti ions to a dose of 1x10(17) ions/cm(2) was completed at room temperature. After annealing at 1100 degreesC in an Ar atmosphere for 2 h, a phase transition from the fluorite structure of ZrO(2) to an isometric pyrochlore structure-type, A(2)B(2)O(7), occurred due to cation ordering. High-resolution TEM revealed nanodomains of pyrochlore, Y(2)(Ti(x)Zr(1-x))(2)O(7), with acongruent to10.24+/-0.05 A. The nanodomains of the pyrochlore phase, embedded within the YSZ fluorite substrate, occurred in a depth range from 45 to 105 nm below the surface, which corresponds to Ti concentrations from similar to10 to similar to15 at. %. The nanoscale pyrochlore precipitates and the YSZ matrix have a completely coherent orientation. (C) 2002 American Institute of Physics.