穩定化之氧化鋯因具有甚低的熱導率，與金屬相近的熱膨脹係數等特性而廣被應用於坩堝、噴嘴、墊片、絕熱材料，以及熱屏障的塗附層。為形成塗附層，須先利用分散劑製備氧化鋯漿料，則漿料之流變性質便成為首要瞭解的研究標的。本研究之目的旨在檢討pH值及常見的分散劑對氧化鋯漿料流變行為的影響。
本研究是以球磨之方式，將起始氧化鋯粉末原料細化，再調整漿料之pH值或添加不同分散劑，探討其流變性質、濁度及ζ電位之間的關係。研究結果顯示，起始粉末原料ZrO2-1（monoclinic）所調配之漿料僅在添加HNO3後，在pH值介於約2.5～4.5時有較佳的分散現象；ZrO2-2（tetragonal）所調配之漿料，在添加0.1wt%陽離子型分散劑Poly(ethyleneimine)時，有較佳的分散性。而其他兩種陰離子型分散劑D305及Darvan 7在各添加0.1、0.5、1.0 wt%時，皆會降低對ZrO2-1及ZrO2-2懸浮液中粉體之ζ電位，進而造成其分散性不良之影響。

Stabilized zirconia is applied to the crucibles, jets, spacers, refractory materials and thermal barrier coatings because the thermal conductivity coefficient of zirconia is quite low, and the thermal expansion coefficient of zirconia is near to that of metals. In order to form thermal barrier coatings, it is necessary to prepare the zirconia suspensions using dispersants. Therefore, understanding the rheological behaviors of suspensions becomes the most important research motive. In this study, effects of different dispersants and pH value on rheological behaviors of zirconia suspensions were investigated.
The particle sizes of zirconia raw materials were reduced by ball milling, and the suspensions were prepared by adjusting pH value or adding various dispersants. The relationships among rheological behaviors, turbidity, and ζ-potential were discussed. The ZrO2-1(monoclinic) suspension showed the better dispersive state in the pH range of 2.5～4.5 after adding HNO3. The ZrO2-2(tetragonal) suspension showed the better dispersive state after adding 0.1wt% poly(ethyleneimine). The addition of 0.1, 0.5, 1.0wt% D305 or Darvan 7 dispersant caused a reduction in the zeta potential of ZrO2-1 and ZrO2-2 because of the worse dispersive state of these suspensions as mentioned.

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