【作者】 庞连云；

【导师】 连峰；

【作者基本信息】 大连海事大学 ， 机械电子工程， 2011， 硕士

【摘要】 钛以其轻质、高比强、高比刚、高耐蚀、无磁性等优异性能被称为“海洋金属”,成为海洋工程,尤其是海洋军事工程中的重要材料。钛合金材料的使用可以大大提高舰船的整体性能,因此开发高性能的钛合金材料可以增强舰船作战能力和降低舰船服役期的成本。空化和空蚀对船舶螺旋桨、海洋工程结构物的有害作用已被充分证明,并且进行了广泛研究。由于超疏水表面具有自清洁、减阻、抑制表面腐蚀和氧化等优点,其在海洋工程领域存在巨大优势。制备超疏水钛合金表面并运用于船体,有望在船舶的抗空蚀方面实现新的突破。但有关表面的润湿性对表面抗空蚀特性的影响的研究还鲜有报道。本文利用激光表面纹理加工和自组装分子膜改变钛合金表面润湿性,研究表面的润湿性对表面抗空蚀特性的影响,为制备新型抗空蚀钛合金材料提供理论依据和技术支持。本文主要工作如下：1、利用激光加工技术在Ti6A14V表面加工点阵状纹理并分别沉积1H,1H,2H,2H-全氟十二烷基三氯硅烷(FDTS)、1H,1H,2H,2H-全氟辛烷基三氯硅烷(FOTS)、三氯十八硅烷(OTS)和3-巯基丙基三甲氧基硅烷(MPS)四种自组装分子膜,从而改变了Ti6A14V的表面润湿性。接触角由大到小的排序为：FDTS>FOTS>OTS>MPS。接触角最大可达到164.5°,形成超疏水钛合金表面。2、将实测接触角与Wenzel模式和Cassie模式计算出的理论接触角比较发现,实测接触角大于150°时接近Cassie模型计算出的接触角,而小于150°时接近Wenzel模型计算出的接触角。改变纹理的间距和选择不同的自组装分子膜,可以控制表面接触角的大小。3、为研究表面润湿性和纹理结构对表面抗空蚀特性的影响,利用激光加工技术在Ti6A14V表面分别加工出直线和网格纹理。沉积FOTS自组装分子膜后,表面疏水性增强,抗空蚀能力提高,且网格纹理的表面抗空蚀能力强于直线纹理的。更多还原

【Abstract】 As having many advantages, Titanium is called "metal of sea". It is the important material in Marine Engineering, especially in the military engineering. It can improve the overall performance of the vessels, Hence, Titanium’s high property can improve capabilities and reduce the cost of the ship.It has been fully proved that cavitation and cavitation erosion are harmful effects for propellers of the ships and the project structure of maritime, and has been extensive studied. In recent years, hydrophobic surface has many advantages, for example, self-cleaning, friction reduction, prevent the surface oxidation corrosion. Especially, it has huge advantages in ocean engineering. Preparing and using superhydrophobicity in vessels is becoming new discover in cavitation about the vessels. But it is few research about the influence of cavitation characteristics of surface wettability.In this paper, Surface wettability of cavitation was transformed by laser surface texture processing and self-assembly molecular membrane, in order to change surface wettability and provide the theory basis and the technical support for making the new cavitation erosion resistance titanium work were did as follows:1、In order to change the surface wettability of Ti6A14V, the Ti6A14V was treated into regular dot matrix structure with lattice structure by laser manufacturing, self-assembled monolayers of FDTS、FOTS、OTS and MPS were prepared on texturing surface by self-assembled method. The contact angle is ranked from big to small: FDTS>FOTS>OTS>MPS. and the maximum angle can reach 164.5°, superhydrophobic surfaces are prepared.2、Comparation of measured contact angles with the contact angles calculated with both models shows that the measured contact angles larger than 150°are close to the contact angles calculated with Cassei model, however, the measured contact angles less than 150°approach the contact angles calculated with Wenzel model. Contact angles can be controlled by adjusting spacing of texture and choosing different self-assembled monolayers.3、in order to explore the effects of surface wettability and laser manufacturing on the characterisitics of cavitation erosion resistance of materials. Line and grid texture are manufactured to Ti6A14V alloy with laser surface modification method. preparing FOTS self-assembled monolayers, the Hydrophobic of the surface was increased, he cavitation erosion resistances of the specimen was improved, and the grid texture is stronger than the line texture.更多还原