Local structures in the Zr-15mol% Fe2O3 system obtained by ball milling

S. FIGUEROA, J. DESIMONI, P. C. RIVAS, M. C. CARACOCHE AND O. DE SANCTIS

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

Año: 2006 vol. 89 p. 3759 - 3764

0002-7820

Local Structures in the ZrO2–15 mol% Fe2O3 System Obtained by Ball Milling Santiago Figueroa,Judith Desimoni,** Patricia C.Rivas,and Maria C.Caracoche     The Mo ¨ssbauer effect and perturbed angular correlation tech- niques have been used to investigate the nature and thermal sta- bility of Zr and Fe surroundings in a solid solution of zirconia and 15 mol%hematite obtained by mechanical mixing.Hema- tite incorporates completely into the zirconia lattice,resulting in a substitutional cubic structure that remains stable over a wide thermal range.Upon annealing at 900 1 a 20%decrease in the iron solubility occurs,accompanied by the cubic to tetragonal zirconia transformation.Both the cubic and the tetragonal crys- talline solid solutions exhibit two local coordinations for each one of the probes.The presence of the charge-balancing oxygen vacancy,which appeared after Fe3 1 substitution for Zr4 1 and located as a nearest neighbor to host and dopant cations,is re- .ected by the most disordered interaction,which shows similar characteristics for the cubic and the tetragonal polymorphs.The other local coordination,described at Zr sites by an electric .eld of phase-dependent intensity,has been thought to depict a direct interaction between very near Fe and Zr cations.