Hyperfine characterization of the metastable t"-form of the tetragonal phase in ZrO2-10 mol% Y2O3 powders synthesized by gel-combustion

M.C. CARACOCHE; J.A. MARTÍNEZ; P.C. RIVAS; A.M. RODRÍGUEZ; D.G. LAMAS; G.E. LASCALEA; N.E. WALSÖE DE RECA

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

Blackwell Publishing

Año: 2005 vol. 88 p. 1564 - 1567

0002-7820

A nanocrystalline ZrO2-10 mol% Y2O3 powder synthesized by a nitrate-citrate gel-combustion process and stabilized in the metastable t"-form of the tetragonal phase has been characterizedusing mainly the Perturbed Angular Correlations technique. The determined hyperfine interaction allows a clear distinction between the zirconium surroundings in the t"-form and those already known of the other forms of the tetragonal phase. Oxygen vacancies movement is revealed as a slow diffusion involving a very small activation energy. As the powder is heated, a transformation is observed to occur around 560°C, which is consistent with a t"-to-cubic transition.