风沙环境下二氧化钛薄膜的冲蚀磨损行为研究

发布时间：2018-05-15 09:17

本文选题：TiO_2薄膜 + 风沙　；参考：《内蒙古工业大学》2017年硕士论文

【摘要】：二氧化钛纳米薄膜具有许多独特的物理化学性能,近年来有关其应用于光催化、太阳能和自清洁等领域的研究越来越多,但目前关于二氧化钛纳米薄膜界面结构及力学性能的研究很少,而这些力学特性对其应用具有重要的影响。对于涂有二氧化钛纳米薄膜的太阳能电池板和玻璃等材料来说,长期在户外恶劣环境下使用,必然会受到风沙的冲蚀和磨损,尤其是在内蒙古中西部等北方多风沙地区,受风沙环境的侵蚀更为严重,必然会缩短二氧化钛纳米薄膜的使用寿命。因此,研究风沙环境下二氧化钛纳米薄膜的冲蚀磨损特性和失效行为,对揭示二氧化钛纳米薄膜受风沙侵蚀的作用机理、评价其耐久性以及进一步改善其性能具有重要的意义。本文通过溶胶-凝胶法,在玻璃表面制备一、三、五层二氧化钛纳米薄膜,研究二氧化钛薄膜对玻璃基体表面抵抗风沙侵蚀的影响。利用傅立叶变换红外光谱仪(FT-IR)、X射线衍射仪(XRD)等分析测试手段系统的研究热处理对二氧化钛薄膜物相组成。结果表明:二氧化钛在300°C时,主要以非晶态的形式存在。随着温度提升到500°C,板钛矿逐渐消失,被新生成的锐钛矿替代。利用辉光显微镜和椭圆偏光测厚仪,对涂覆一、三、五层的TiO_2薄膜厚度进行了测定。结果表明:随着薄膜层数的增加,其厚度逐渐的均匀增加。利用气流挟沙喷射法对涂膜玻璃进行冲蚀实验,通过控制风沙流速、沙剂量、冲蚀角度等变量,真实模拟了实际的风沙环境。采用扫描电镜(SEM)研究了TiO_2薄膜在风沙环境下的冲蚀磨损特性、冲蚀行为和侵蚀机理。并通过质量失重法,评价了薄膜材料抗风沙冲蚀的特性。结果显示:TiO_2薄膜磨损量随着冲蚀速度和沙剂量的增加而增加;而随着薄膜厚度的增加,磨损量逐渐减小;其侵蚀机理为:在低角度冲蚀下,薄膜主要受到微切削作用下产生的划痕损伤,而在高角度冲蚀下,主要受到冲蚀挤压变形作用下产生的材料破损。同时TiO_2薄膜不仅强度高而且脆性强,其在高角度冲蚀下的磨损更为严重。利用Fluent软件模拟风沙对涂覆TiO_2薄膜玻璃的冲蚀过程,运算得出风沙对靶材的侵蚀率,所得数据与试验结果进行对比。结果表明:试验数据与模拟数据虽有较大误差,但是整体数据趋势相同,误差可以接受,为其冲蚀行为可以提供有利的预测与判断。
[Abstract]:Titanium dioxide nanocrystalline films have many unique physical and chemical properties. In recent years, there have been more and more researches on their applications in photocatalysis, solar energy and self-cleaning. However, there are few studies on the interface structure and mechanical properties of TIO _ 2 nanocrystalline films, and these mechanical properties have an important impact on its application. For materials such as solar panels and glass coated with titanium dioxide nanocrystalline films, long-term use in harsh outdoor environments will inevitably result in erosion and wear by wind sand, especially in windy and sandy areas in the central and western parts of Inner Mongolia. The erosion caused by wind and sand environment is more serious, which will shorten the service life of TIO _ 2 nanocrystalline film. Therefore, it is of great significance to study the erosion and wear characteristics and failure behavior of TIO _ 2 nanocrystalline films in wind-sand environment, to reveal the mechanism of wind erosion, to evaluate its durability and to further improve its performance. In this paper, one, three and five layers of TIO _ 2 nanocrystalline films were prepared on glass surface by sol-gel method. The effect of TIO _ 2 film on the surface of glass substrate against wind erosion was studied. The phase composition of titanium dioxide thin films was studied by means of Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD). The results show that titanium dioxide mainly exists in amorphous form at 300 掳C. As the temperature rises to 500 掳C, the plate titanite disappears and is replaced by the newly formed anatase. The thickness of TiO_2 film coated with one, three and five layers was measured by means of glow microscope and ellipsometer. The results show that the thickness of the films increases uniformly with the increase of the number of layers. The erosion experiment of coated glass was carried out by means of airflow sand carrying spray method. The actual wind-sand environment was simulated by controlling wind sand velocity, sand dose, erosion angle and other variables. The erosion wear characteristics, erosion behavior and erosion mechanism of TiO_2 films in wind-sand environment were studied by SEM. The erosion resistance of thin film materials to wind and sand was evaluated by mass loss method. The results show that the wear amount increases with the increase of erosion velocity and sand dose, but decreases with the increase of film thickness. The film is mainly scratched by micro-cutting, while the material is damaged by erosion and extrusion under high angle erosion. At the same time, the TiO_2 film not only has high strength and brittleness, but also has more serious wear under high angle erosion. The erosion process of TiO_2 thin film glass coated with wind sand was simulated by Fluent software, and the erosion rate of wind sand to target was obtained by calculation. The results were compared with the experimental results. The results show that although there is a large error between the experimental data and the simulated data, the overall data trend is the same and the error is acceptable, which can provide favorable prediction and judgment for the erosion behavior of the test data.
【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ134.11;TB383.2

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