| In this paper, Zirconia fiber green body was prepared with extrusion-conglomeration molding sucessfully, using Zirconium water based slurry made of partial stabilized Zirconia super fine powder. The molding mechanism, influence factors on preparation of Zirconia fiber, grains growth kinetic and sintering kinetics of Zirconia fiber during sintering were studied systematically.All of achievements of this study were obtained as follows: extrusion-conglomeration molding for forming Zirconia fiber was put forward for the first time. The molding mechanism was discussed at the same time. When the Zirconium slurry was displaced into conglomerating solvent with low dielectric constant and mutual solubility to water, Zirconia particles would conglomerate because of the electric double layer being thin rapidly, static repulsive falling and equipment breaking among Zirconia particles. When the conglomeration generated continuously, zirconium slurry passed through spinneret orifice changed from fluid state to solid state and become Zirconia fiber with slenderness ratio. In addition, water in Zirconia slurry was extracted and remained little, and conglomerating solution with minute surface tension around Zirconia fiber. During drying process, adhesion between two Zirconia fibers was avoided.The explain of forming coarseness on Zirconia fiber green body surface was given as follows: first, the interfacial tension between organic solvent and Zirconia slurry result in water in film around grains surface was extracted instantly and driver force for decreasing surface area and forming a smooth surface became faintness result in minute surface tension of conglomerating solvent. So that the non-uniform surface created by slurry flowing was kept. Second, when Water, extracted from fiber interior by conglomerating solvent continuously, numerous capillary generated and they looked like minute protuberance at macroscopic. Third, slurry streamlet expanded slightly for the reason of the Barus effect after leaving the spinneret orifice. This expander made the coagulated surface cracked and generated some minute crannies and they looked like minute protuberance at macroscopic as well.The hole appeared in fiber center was because of that the particles were carried by water from slurry center to surface due to water differential concentration between solvent and interior of slurry. On the other hand, the slurry exterior surface was solidified already, so the shrinkage generated just from interior to surface of fiber.Forming optimum parameters of preparation of Zirconia fiber were given such as, In 47vol% slurry, the amount of dispersant agent PAANH4 was about 0.7 wt.% of Zirconia powder and milling time was about 24h. Acetone was used as the conglomerating agent. Extrusion press was from 3.28 KPa to 4.92 KPa. The Zirconia fiber was sintered at 1530℃for soaking 300min and it's density is about 6.05g/cm~3.Zirconia fiber's grain growth kinetic was studied and the grain growth activation energy was calculated according to the law of Zirconia fiber's grain size change during sintering. Further more, the sintering kinetic of Zirconia fiber was studied via the change of fiber density during sintering. The result shows that sintering process of Zirconia fiber is similar to block materials.The sintering of Zirconia fiber aggregation was also studied in this paper. The result showed that, neck between two pieces of fiber could be observed after sintering in aggregation made of Zirconia fiber green body. If the aggregation made up of Zirconia fiber fired at 1530℃for soaking 300min, there were small shrinkage of aggregation but the neck between two pieces of fibers was observed hardly.
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