Preparation of Y2O3 stabilised ZrO2 ceramic nanopowders by surface doping

Weakly agglomerated nanocrystalline Y2O3-ZrO2 powder was prepared by disper sion Y2O3 on the surface of ZrO2 nanopowder (7.3 nm) that was derived from gas phase synthesis. The utmost dispersion capacity of Y2O3 on the surface of ZrO2 was determined to be 0.16 gY(2)O(3)/gZrO(2) (or 8.7 mol.-%Y2O3-ZrO2 ) which suggests that 3 mol.-%Y2O3 would be homogeneously dispersed on ZrO2 and no phase segregation would occur during surface doping. The results sh ow that the tetragonal phase content in surface doped ZrO2 increased with g rain growth or heating temperatures, unlike the undoped and the bulk doped ZrO2. The stabilisation of the tetragonal phase resulted from the incorpora tion of Y3+ cations from the surface into the grains of ZrO2. This conclusi on is supported by the X-ray photoelectron spectroscopy and X-ray diffracti on evidence. Surface doped powders have a strong tendency to improve the an ticoarsening ability and suppress grain growth, especially at higher doping levels and at lower heating temperatures.