کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1464982 | 989676 | 2010 | 4 صفحه PDF | دانلود رایگان |

Zirconia–silica (50/50 vol.%) nanocomposites were prepared by supercritical CO2 method at 15 MPa and 150 °C. The characterization of synthesized powders was carried out by X-ray diffraction (XRD), transmission electron microscopy (TEM) scanning electron microscopy (SEM) and BET. The results of XRD showed that the nanocomposite powders have mostly the tetragonal phase of zirconia (t-ZrO2) at 1000 °C, however it was determined the tetragonal (major), monoclinic (minor) of zirconia and cristobalite (major) phases of silica were present at 1500 °C. The crystallite sizes of the t-ZrO2 were in the range of 8–30 nm with increasing temperature from 1000 °C to 1500 °C. The surface area of samples at 1000 °C was 171 m2/g. In addition, the agglomeration degree (N=dBET3/dXRD3) of powders at 1000 °C was 4, which was an indication of the soft agglomeration of powders. The stabilization of the t-ZrO2 up to 1500 °C was attributed to the confinement of ZrO2 particles by the surrounding cristobalite phase of silica in the structure.
Journal: Ceramics International - Volume 36, Issue 7, September 2010, Pages 2231–2234