Effect of iron impurity on structural development in ball-milled ZrO2–3mol% Y2O3

Abstract Powders Mixture of monoclinic ZrO 2 and 3 mol% Y 2 O 3 were prepared by high-energy ball milling. Ball-milled products were investigated by means of X-ray diffraction, Rietveld refinement, spectrophotometry and Mossbauer spectroscopy. The tetragonal Zr 1– x Y x O 1.982 ( x =0.037) was formed within 30 min of ball milling in which the crystallite size decreases up to 13 nm and appears almost unchanged even after 30 h of milling. Peak intensities of the monoclinic phase decrease and disappear after 10 h of milling. The unit cell-volume of tetragonal phase decreases with increasing iron content incorporated from milling media. In the calcined product ball-milled for 30 h the monoclinic phase takes place in the range 700–900 °C and disappears at 1100 °C due to the presence of Y 3+ cations. It was concluded that at room temperature, the stabilization of tetragonal phase at the beginning of milling process was attributed to the substitutional Fe 3+ cations, while the hematite Fe 2 O 3 was formed at the end of ball milling.