氧化钛纳米陶瓷的制备及其结构与力学性能  

Preparation,microstructures and mechanical properties of TiO_2 nanoceramics

作　　者：冶银平[1] 李建功[2] 陈建敏[1] 周惠娣[1] 

机构地区：[1]中国科学院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [2]兰州大学材料科学与工程研究所,甘肃兰州730000

出　　处：《中南大学学报（自然科学版）》2008年第4期682-687,共6页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50575217);国家创新群体基金资助项目(50421502)

摘　　要：为探讨在无压烧结过程中TiO2纳米陶瓷的致密化与晶粒长大的关系以及纳米陶瓷的结构对其力学性能的影响,采用溶胶-凝胶技术制备的不同颗粒粒径的TiO2纳米粉体经冷压成型后无压烧结TiO2纳米陶瓷。研究结果表明:利用相变辅助无压烧结方法在800℃烧结获得了晶粒粒径小于60nm、相对密度超过95%的TiO2纳米块体陶瓷;当800℃以下烧结时,TiO2纳米陶瓷的相对密度随烧结温度的升高而快速增大,而TiO2纳米陶瓷的平均晶粒粒径随烧结温度升高则缓慢长大;当大于800℃的温度烧结时,TiO2纳米陶瓷的致密化加快,但陶瓷的晶粒粒径则快速长大。TiO2纳米陶瓷的显微硬度主要取决于TiO2纳米陶瓷的相对密度和平均晶粒粒径,即纳米氧化钛陶瓷的相对密度越大,晶粒粒径越小,则显微硬度越大。In order to inquire into the processes of densification versus grain growth and the effect of the microstructure on the mechanical property of the TiO2 nanoceramics, the TiO2 nanopowders with various mean particle sizes synthesized by sol-gel method were used to sinter bulk TiO2 nanoceramics. The results show that the bulk TiO2 nanoceramics with an average grain size of less than 60 nm and a relative density over 95% are prepared by a phase-transformation-assisted pressureless sintering method at 800 ℃. The relative density of the TiO2 nanoceramics increases rapidly whereas the average grain size increases slowly with the increase of sintering temperature below 800 ℃. The higher sintering temperature above 800 ℃ enhances the densification of the TiO2 nanoceramics, but increases intensively the average grain size of the TiO2 nanoceramics. The Vickers microhardness of the TiO2 nanoceramics is mainly related to the relative density and average grain size of the TiO2 nanoceramics. Namely, the Vickers microhardness increases with the increase of relative density and the decrease of the average grain size.

关 键 词：TiO2纳米陶瓷 晶粒生长 致密化 显微硬度 

分 类 号：TQ174[化学工程—陶瓷工业]