用Sol-Gel法制备钛酸铝微粉及其低膨胀陶瓷合成

Preparation of Aluminium Titanate Micropowder by Sol-Gel Method and Improvement of Aluminium Titanate Ceramics

利用１ＨＮＭＲ、ＩＲ、ＤＴＡ／ＥＧＤ／ＧＣ、ＴＧ、ＡＡＳ、ＰＳＤ和ＳＥＭ 手段，研究了Ａｌ（ＯＮ３）３·９Ｈ２Ｏ乙醇溶液与钛酸丁脂混合液的反应机理，钛酸铝晶相形成过程中晶相的变化及其陶瓷的热膨胀性。实验结果表明，形成整体凝胶的溶胶其［Ａｌ３＋ ］∶［Ｔｉ４＋ ］之比接近于理论值。主晶相钛酸铝的形成温度为１ ３００℃。１ ４００℃焙烧过的粉体其平均粒径为３．６μｍ ，经１ ４５０℃烧结后陶瓷的热膨胀系数为０．４１×１０－ ６／Ｋ。

By means of 1HNMR, IR, DTA/EGD/GC, TG, ASS, PSD and SEM, the reaction mechanism between Al(NO 3) 3·9H 2O and the mixture of Ti(OC 4H 9), C 4H 9OH and CH 3COOH in C 2H 5OH, with or without the additives was investigated. Furthermore, the phase transformation of AT(Al 2TiO 5) gel at different temperature and the particle size distribution of AT powder calcinated at 1 400℃ for 2h as well as the thermal expansion of AT ceramics sintered at 1 450℃ for 2h were also studied. The experimental results showed that the gel composite was homogeneous and approximately approached to [Al 3+ ]∶[Ti 4+ ]=2∶1. The temperature of main crystalline phase AT formation was 1 300℃. Average size of AT powder calainated at 1 400℃ for 2h was 3.6μm. The crystalline size and thermal expansion cofficient of AT ceramics sintered at 1 450℃ for 2h was 2~6μm and 0.41×10 -6 /K, respectively.