Preparation and characterization of zirconia-yttria porous ceramics with addition of potassium iodide

Porous zirconia stabilized with 8 mol% of yttria were prepared by adding different amounts of KI followed by its removal upon sintering. The thermal removal was evaluated by thermogravimetric and differential thermal analysis and dilatometric measurements. The samples were prepared and sintered at 1400 deg C/2h. All samples were characterized by X-ray diffraction and topographic analysis of polished and thermally etched surface to evaluate pore content. The additive content was evaluated by X-ray fluorescence analysis, showing that KI was removed during sintering. The electrical behavior was analyzed by impedance spectroscopy. The X- ray diffraction analyses show that all samples are single phase, cubic fluorite-type. The impedance diagrams allowed evaluating the increase in intergranular and intragranular resistivity with increasing content of pores. (author)