纳米Fe_2O_3对钛酸铝陶瓷热稳定性能的影响

Effect of Iron Oxide Nanoparticles on Thermal Stability of Aluminium Titanate Ceramics

以溶胶–凝胶法制备的钛酸铝前驱体和固相合成法制备的纳米Fe2O3为原料,在不同温度煅烧保温2h制备出钛酸铝固溶体[Al2(1–x)Fe2xTiO5]。通过X射线衍射、电子探针分析并计算晶格常数和热分解率,研究了纳米Fe2O3含量以及烧成温度对烧后试样热分解性能的影响。结果表明:纳米Fe2O3很容易与Al2TiO5反应,形成固溶体,抑制钛酸铝陶瓷的热分解;随着纳米Fe2O3加入量的增加,Al2(1–x)Fe2xTiO5的晶格常数变大,热分解率降低,但当加入量超过10%时,Al2(1–x)Fe2xTiO5的晶格常数不变甚至减小,热分解率反而会增大;纳米Fe2O3作为添加剂可改善钛酸铝陶瓷的热分解性能。煅烧温度对钛酸铝的热分解率有很大影响,随着温度升高,热分解率降低,当温度大于1350℃时,钛酸铝陶瓷晶格常数保持不变,钛酸铝陶瓷的热分解率变化不大。

The aluminum titanate solid solution[Al2（l-x）Fe2xTiO5] was prepared using synthesized precursors of aluminum titanate （Al2TiO5） and synthesized iron oxide （Fe2O3） nanoparticles by solid state reaction as starting materials, firing at different temperatures for 2 h. The effect of Fe2O3 nanoparticles content and fired temperature on thermal stability of aluminium titanate ceramics was investigated by X-ray diffraction, electron probe micro-analyzer and calculation of their lattice constant and thermal decomposition. The results showed that 1） Fe203 nanoparticles was reacted with A12TiO5 easily, thermal decomposition of aluminium titanate ceramics can be reduced by doping Fe203 nanoparticles with the formation of solid solution; 2） The lattice constant of A12（l-x）Fe2xTiO5 increased and thermal decomposition decreased gradually as the Fe2O3 nanoparticles content increasing, but the lattice constants of A12（1-x）Fe2xTiO5 remained unchanged or decreased and thermal decomposition increased as the Fe2O3 nanoparticles content exceed 10%; 3） The fired temperature of lattice ceramics affects its thermal decomposition greatly in improving thermal stability by doping Fe2O3 nanoparticles, thermal decomposition decreased gradually with a rise temperature, whereas thermal decomposition had no significant change when the fired temperature exceeds 1350℃.