China Nonferrous Metallurgy

Scandia-stabilized zirconia (ScSZ) composite powders with different scandium content had been successfully prepared by co-precipitation method，using zirconium oxychloride and scandium oxide as raw materials, polyethyleneglycol (PEG800) as dispersant and ammonia as precipitant. The synthesized samples were characterized by means of TG/DSC、ICP、XRD、Raman and SEM. The influence of the doping scandium on the thermal stability of ZrO₂ precursor, the phase and morphology of ZrO₂ powder were systematically investigated. The influence of washing method on the morphology of ScSZ powder was also discussed. The ZrO₂ and ScSZ precursor were amorphous. The results demonstrated that the total weight loss of ScSZ precursor was greater than that of ZrO₂ precursor. And the diffraction peaks of the ScSZ powder were sharp after calcination, which were indexed to a mixture of the tetragonal and cubic ZrO₂ phases. The diffraction peaks of ZrO₂ powder was corresponding to the monoclinic ZrO₂ phase. The results showed that scandium doping promoted the transformation from monoclinic to tetragonal and cubic phases. Scandium doping has no obvious effect on the particle size of ZrO₂ powder, and the ZrO₂ and ScSZ powder displayed agglomerated morphology with particle size ranging from 0.5 to 3μm. Washing the powder with ethanol was conducive to reducing the primary particle size and agglomeration phenomenon of the ScSZ powder, and the agglomeration was relatively loose.