A sedimentation method from liquid suspensions has been examined to prepare thin films of yttria stabilized zireonia (YSZ). Employment of a poly(accylic acid) ammonium salt as a dispersing agent was effective for suspending the raw YSZ powder in water. A well sintered, self-supporting YSZ thick film with a relative density of ca. 97 could be obtained after a thick cake layer precipitated from aconcentrated YSZ suspension of 50 g dm-3 was sintered at 1300 deg.C. On the other hand, when an acrylic emulsion as a binder was added into in the YSZ suspension, a number of pores formed in the sintered YSZ thick film and the relative density was as low as ca. 92, despite the increased negative reta potential of the suspension, probably due to aggregation of YSZ particles. Fabrication of YSZ thin films was examined by sedimentation from a dilute YSZ suspension (2.0 8 dm-3) containing the disporsing agent for 3 days on a flat and porous substrate of La_0.8Sr_0.2zMnO3 as an air-side electrode of SOFC, followed by firing at 1300 deg. C for 3 h. As a result, a well sintered YSZ film of about 1.5 mu m thick could be fabricated when the suspension was allowed to stand for 2 days prior to sedimentation to eliminate large particles. The average grain size of YSZ in the film was 3-4 mu m. The well-sintered films showed almost negligible nitrogen gas permeation at room temperature under an initial pressure difference of 4 x 10~4 Pa.
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机译：已经研究了从液体悬浮液中沉淀的方法，以制备氧化钇稳定的氧化锆（YSZ）薄膜。使用聚（乙酸）铵盐作为分散剂对于将粗制YSZ粉末悬浮在水中是有效的。烧结良好的，自支撑的YSZ厚膜，相对密度为。在50℃dM-3的浓缩YSZ悬浮液中沉淀出的厚饼层在1300℃下烧结后，可得到97。另一方面，当将作为粘合剂的丙烯酸乳液加入到YSZ悬浮液中时，在烧结的YSZ厚膜中形成的孔的数量和相对密度低至约1。 92，尽管悬浮液的负离子强度增加，可能是由于YSZ颗粒的聚集。通过在含有SOFC空气侧电极的La_0.8Sr_0.2zMnO3的平坦多孔衬底上，从含有分散剂的稀释YSZ悬浮液（2.0 8 dm-3）中沉淀3天，来检查YSZ薄膜的制备。在1300度射击C持续3小时。结果，当使悬浮液在沉淀之前静置2天以消除大颗粒时，可以制造约1.5μm厚的烧结良好的YSZ膜。膜中YSZ的平均晶粒尺寸为3-4μm。良好烧结的薄膜在4 x 10〜4 Pa的初始压差下，在室温下的氮气渗透几乎可以忽略不计。
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