Thermal annealing of single crystal zirconia implanted with platinum ions

Single crystal samples of (100) oriented cubic zirconia stabilised with 9.5 mol% yttria were implanted with platinum ions, using a metal vapour vacuum arc (MEVVA) high current ion implanter, to a nominal dose of 1x1017 ions/cm2. The implanted samples were annealed isothermally in air ambient at 400-1200 C, from 1 to 24 h. Rutherford backscattering spectrometry and channelling (RBSC) of 2 MeV He ions are employed to determine depth distributions of ion damage, Pt ions and substitutionality of Pt ions before and after annealing. As implanted samples do not show an amorphous phase, the retained dose is small, about 35% of the nominal dose, and the Pt depth profiles are sputter limited. Ion damage begins to anneal at 400 C and eventually recovers quite well at 1200 C, leading to the formation of partially coherent precipitates of Pt. Platinum shows a solid solubility of at least 13 mol.% in zirconia at 1200 C. At lower anneal temperatures, cubic zirconia may have transformed to monoclinic or tetragonal phases. ((orig.))