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利用热膨胀方法，研究了冷却速度对热压烧结的ＺｒＯ２陶瓷（含２ｍｏｌ％Ｙ２Ｏ３稳定剂）正方相（ｔ）到单斜相（ｍ）转变的影响．结果表明：冷却速度可以改变ｔ－ＺｒＯ２相含量，这与ｔ→ｍ转变受热激活控制有关．随冷却速度增加相变开始Ｍｓ下降，结束点Ｍｆ上升．ＴＥＭ观察表明ｍ相的长大速度较钢铁中马氏体慢得多．电子束照射下诱发ｍ相生长说明新相长大必须越过一个能垒．
The effect of cooling rate on the transformation from orthorhombic phase (t) to monoclinic phase (m) of hot-pressed ZrO2 ceramics (containing 2mol% Y2O3 stabilizer) was studied by means of thermal expansion method. The results show that the cooling rate can change the content of t-ZrO2 phase, which is related to the activation of t → m transition. As the cooling rate increases, Ms begins to decrease and Mf increases at the end point. TEM observations show that the m-phase grows much slower than the martensite in steel. Induced m-phase growth under electron beam irradiation shows that the new phase must pass over an energy barrier.