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毕业论文-硬脂酸凝胶法制备出纳米TiO2粉体及陶瓷，共38页，16144字
摘 要
以钛酸四丁酯为原料，用硬脂酸凝胶法成功的制备出纳米TiO2粉体，并分别采用了相变辅助烧结法和两步烧结法制备出纳米TiO2陶瓷。利用差热分析 (DTA)、 X射线衍射(XRD)、透射电镜(TEM)测试技术对纳米TiO2粉体和陶瓷进行了表征，结果表明：相同煅烧温度下，加入硬脂酸比例越大，晶粒尺寸越小；加入硬脂酸相同时，温度越高，晶粒越大。在硬脂酸和钛酸四丁酯质量比为1:1.5、1:2，400℃、500℃煅烧保温2小时，都为锐钛矿相，晶粒大小为8-18nm。550℃煅烧时出现金红石相，含量为18%，且随温度升高而增加。利用相变辅助烧结和两步烧结法都能得到相对密度80%-98%的纳米TiO2陶瓷：500℃煅烧的粉体烧结成陶瓷后仍全为锐钛矿相，晶粒大小分别为18.8nm、17.7nm；550℃煅烧的粉体烧结成陶瓷后，锐钛矿含量约为70%，晶粒大小分别为28.7nm、32.1nm，金红石相含量约为30%，晶粒大小为83.3nm、149.9nm。
关键词：硬脂酸凝胶法；纳米TiO2粉体；纳米TiO2陶瓷；相变辅助烧结；两步烧结法
ABSTRACT
In this paper, TiO2 nanocrystalline powder were successfully prepared by the stearic acid meathod, using tetrabutyl titanate as raw materials. TiO2 nanoceramic were successfully prepared by phase transformation assisted sintering  Two-step sintering, respectively. The samples were characterized by DTA, XRD and TEM. The results showed that the crystalline size of TiO2 decrease with the increase of stearic acid content and increase with the increase of calcining tempreture; the samples are all anatase at the ratio of stearic acid to tetrabutyl titanate 1:1.5 and 1:2 ,at 400℃and 500℃ calcination hold by 2 hours. The crystalline size of TiO2 are 8-18nm. The rutile content is 18% at 550℃ hold by 2 hours and increases with the increasing tempreture. TiO2 ceramic prepared respectively by phase transformation assisted sintering and Two-step sintering are both nanoceramic, the relative density is 80%-98%. The nanoceramic prepared by the powder of 500℃ calcination is both anatase and the crystalline size are 18.8nm, 17.7nm, respectively. 70% in the nanoceramic prepared by the powder of 550℃ calcination is anatase and the crystalline size are 28.7nm, 32.1nm, 30% is rutile and the crystalline size are 83.3nm, 149.9nm.
Key words：TiO2 nanopowder; Stearic acid method; TiO2 nanoceramic; Phase transformation assisted sintering; Two-step sintering;
目 录
摘 要 I
ABSTRACT II
1.1 引言 1
1.2纳米材料发展历程 1
1.3纳米材料的奇异效应 1
2二氧化钛的性质及用途 3
2.1二氧化钛的晶格结构 3
2.2二氧化钛的用途 4
3纳米陶瓷 5
3.1纳米陶瓷性质和用途 5
3.1.1纳米陶瓷的力学性能 5
3.1.2纳米陶瓷的应用 6
3.2纳米陶瓷制备 6
3.2.1工艺关键 6
3.2.2纳米陶瓷粉体的制备方法 6
3.2.2.1气相法 6
3.2.2.2液相法 7
3.2.2.3固相法 8
3.2.2.4制备纳米粉体各种方法的优缺点 9
3.2.2.5本实验所采用方法 9
3.2.3 纳米陶瓷的成型 9
3.2.4 纳米陶瓷的烧结 9
3.2.5本实验所用方法 10
4实验部分 11
4.1实验仪器 11
4.2实验药品 11
4.3实验过程 12
4.3.1采用硬脂酸法凝胶法合成纳米TiO2粉体 12
4.3.2采用相变辅助烧结和两步烧结制备纳米TiO2陶瓷 13
5结果分析 13
5.1 纳米TiO2粉体XRD分析 13
5.1.1 XRD分析原理 13
5.2.2分析实验结果 14
5.2纳米TiO2粉体样品的TEM分析 24
5.3纳米TiO2粉体样品的HRTEM分析 25
5.4纳米TiO2粉体的差热（DTA）图 26
5.5纳米TiO2陶瓷的XRD分析 26
5.6纳米TiO2陶瓷烧结收缩率及致密度的分析 30
参 考 文 献 33
致 谢 35