PREPARATION of ALUMINUM TITANATE FILM VIA NONHYDROLYTIC SOL–GEL METHOD AND ITS FUSED SALT CORROSION RESISTANCE

采用非水解溶胶–凝胶工艺,以无水三氯化铝和四氯化钛为前驱体,乙醇为氧供体,环保型高沸点二元酸酯混合物AgSE为溶剂,四丁基溴化铵为稳定剂,在碳化硅基片上制备出均匀、致密的钛酸铝薄膜。借助差热–热重、X射线衍射、场发射扫描电镜和扫描电镜等研究了钛酸铝干凝胶热处理过程中的相变化、钛酸铝薄膜的晶相组成、显微结构及其抗硝酸钠熔体腐蚀性能。结果表明:在750℃低温制备的钛酸铝薄膜晶粒约为10nM,薄膜具有良好的抗硝酸钠熔体腐蚀性能;热处理温度提高到1350℃后,钛酸铝薄膜的晶粒增大至120nM左右,晶界面积急剧减小,无定形相消失,钛酸铝薄膜的抗硝酸钠熔体侵蚀性能大大提高。The homogeneous dense aluminum titanate film was coated on the silicon carbide substrate via nonhydrolytic sol–gel method (NHSG), using anhydrous aluminum chloride and titanium tetrachloride as the precursors, ethanol as oxygen donor, binary mixed ester AGSE with the characteristic of environmental protection and high boiling point as solvent, and tetrabutyl ammonium bromide as stabilizer.The phase transformation of Al2TiO5 xerogel during heat treatment, the crystal composition and microstructure of Al2TiO5 film and its corrosion resistance to fused sodium nitrite were studied by means of differential thermal analysis–thermogravimetry, X-ray diffraction, field emission scanning electron microscopy and scanning electron microscopy.The results show that Al2TiO5 film annealed at 750 ℃ has the crystal size of about 10 nm and possesses good corrosion resistance to the fused sodium nitrite; the crystal size will grow to 120 nm or so when the heat treatment temperature increases to 1 350 ℃.The performance of Al2TiO5 film heat-treated at 1 350 ℃ will be greatly improved due to both sharp decrease of the grain boundary area and the dis-appearance of amorphous phase.国家自然科学基金(50762005;50962006);中国科学院特种无机涂层重点实验室开放基金资助项

Preparation of Aluminum Titanate Film by Sol-gel Method and Its Fused Salt Corrosion Resistance

以钛酸四丁酯和硝酸铝为原料,乙醇为溶剂,通过溶胶-凝胶法在碳化硅基片上制备钛酸铝薄膜。借助dSC-Tg、Xrd、fE-SEM和SEM研究了钛酸铝干凝胶在热处理过程中的热重效应与相变化、薄膜的晶相组成、显微结构及其抗硝酸钠熔体腐蚀性能。结果表明:制备的钛酸铝薄膜表面均匀、致密,晶粒尺寸在100nM左右,具有良好的抗硝酸钠熔体腐蚀性能。Aluminum titanate ( AT) film coated on the surface of SiC substrate was prepared via Sol-gel method,using tetrabutyl titanate and aluminum nitrate as raw materials,ethanol as solvent.The weight loss and phase transformation of AT xerogel during the heat treatment,the crystal composition and microstructure of the AT film and its corrosion resistance to fused sodium nitrite salt were studied by means of DSC-TG,XRD,FE-SEM and SEM.The results show that the prepared AT film is uniform and dense with the crystal size of about 100 nm,and has good corrosion resistance to fused sodium nitrite.国家自然科学基金(No.50762005;No.50962006);中国科学院特种无机涂层重点实验室开放基