钛基体超疏水表面的刻蚀法制备及其性能研究

发布时间：2018-11-11 10:41

【摘要】：由于比强度高、耐腐蚀性好、生物相容性优异等特点,钛及其合金被广泛应用于航空、船舶、生物医学等领域。如何快捷有效地在钛基表面上实现超疏水性能,特别是具有防覆冰和良好机械性能的超疏水钛表面,一直是学术和工业界所关注的问题。目前已有的钛及其合金超疏水表面的制备方法均具有实验成本较高、仪器要求特殊或者操作过于复杂、周期较长等缺点。因此,本文将探索出两种简单有效的超疏水性钛表面制备方法,并研究其抗覆冰性能和耐机械性能。主要研究内容如下:(1)结合双氧水刻蚀和表面修饰的方法在钛基底上制备了超疏水表面。该方法制备试样的疏水性能会随着刻蚀时间延长变得更佳,最后趋于平缓。通过分析疏水性能随刻蚀时间变化的原因,并考虑其疏水性和实验周期,发现最佳刻蚀反应时间为2天。该方法制备的超疏水表面具有良好的自清洁效应。进一步通过使用冰箱模拟低温自然环境条件,对双氧水刻蚀法制备的超疏水表面进行了抗结冰测试发现:在-9.5℃、相对湿度45%条件下,体积为30μL自来水滴的结冰时间要比预处理试样上的液滴延长近一个小时(55.6min)。(2)结合硫酸刻蚀和表面修饰的方法在钛基底上制备了超疏水表面。通过比较不同刻蚀条件下试样的接触角,得出硫酸刻蚀法制备超疏水表面的最佳实验参数为:72%的硫酸浓度、120℃的刻蚀温度、30min的刻蚀时间。通过对不同时间刻蚀后试样的微观形貌进行分析,发现刻蚀30min的试样产生了类农田形结构,并随着晶面不同而产生不同内部形貌,如类蜂窝状、类波浪形等形貌,这些结构均会使得表面粗糙度变大,从而使其超疏水性能变佳。进一步探索该超疏水表面的耐磨损性能,发现所制备的超疏水表面具有较低的摩擦系数。最后通过抗结冰测试,发现水滴在超疏水表面的结冰时间比预处理试样上的水滴延长一个小时以上(67.2min)。(3)进一步通过拉伸试验对制备的超疏水试样进行耐机械性能测试,结果表明:随着预应变的增大,其接触角和滚动角分别减小和增大,但这种变化并不显著,即超疏水性能只有轻微下降。通过分析超疏水拉伸试样微观形貌随预应变的变化趋势发现,随着预应变的增大,一方面类农田结构边界处的间距会增大,另一方面农田内部结构间距也会增大,导致其粗糙度减小,从而使其疏水性能略有下降。
[Abstract]:Titanium and its alloys are widely used in aviation, ship, biomedicine and other fields because of their high specific strength, good corrosion resistance and excellent biocompatibility. How to quickly and effectively realize superhydrophobicity on titanium substrate, especially the super-hydrophobic titanium surface with anti-icing and good mechanical properties, has always been concerned by academic and industry. The methods of preparing superhydrophobic surface of titanium and its alloys have many disadvantages, such as high cost of experiment, special instrument requirement or complicated operation, long period and so on. Therefore, two simple and effective methods for preparation of superhydrophobic titanium surface are explored in this paper, and their ice resistance and mechanical properties are also studied. The main contents are as follows: (1) superhydrophobic surface was prepared on titanium substrate by hydrogen peroxide etching and surface modification. The hydrophobicity of the sample prepared by this method will become better with the increase of etching time, and finally it will become flat. By analyzing the reason why hydrophobicity varies with etching time and considering its hydrophobicity and experimental period, it is found that the optimum etching time is 2 days. The superhydrophobic surface prepared by this method has good self-cleaning effect. Furthermore, the ice resistance of superhydrophobic surface prepared by hydrogen peroxide etching was tested by using refrigerators to simulate the natural conditions at low temperature. It was found that under the conditions of -9.5 鈩，

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