共沉淀喷雾干燥法制备YSZ粉料及其对烧结密度的影响

PREPARATION OF YSZ POWDER BY COPRECIPITATIONSPRAY DRYING METHOD AND ITS EFFECT ON SINTERING DENSITY

用共沉淀结合喷雾干燥法制得了可直接用于煅烧、成型的Y_2O_3稳定的ZrO_2粉料。用扫描电镜观察了喷雾干燥得到的粉料团聚体的尺寸、形貌,以及与喷雾干燥条件的关系。发现了共沉淀悬浮液的球磨对喷雾干燥后粉料的热行为的影响。喷雾干燥制得的粉料在1350、1500℃烧结后,相对密度分别达96.5％、97.8％;而烘箱干燥的粉料在相应温度下烧结,相对密度只达88％、93％。

YSZ(Y_2O_8 stabilized ZrO_2)powder was prepared by the coprecipitation-spray drying method, which can be used directly for calcination and moulding. Such powder obtained can be dry-pressed directly without grinding or crushing. The agglomerates formed during spray drying were observed by SEM. The size ot the agglomerates is related to the spray drying conditions. Relative density of such powder, prepared under a proper apray, drying condition and sintered at 1350℃ and 1500℃ for 2h, can reach 96.5% and 97.8% of the theoretical value, respectively; but the powder prepared by oven-drying can only reach 88% and 93% at the same sintering temperatures.