仿生疏水表面飞秒激光制备研究

发布时间：2018-02-04 07:47

本文关键词： 飞秒激光表面形貌条纹结构驼峰结构　出处：《合肥工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：超疏水表面是指与水接触角大于150°且滚动角小于10°的表面,而形成超疏水表面主要因素是微结构和低表面能,其中微结构由于具有特定的物理或化学性能起到至关重要的作用,基于相关研究结果,在材料表面构造微纳结构对提升疏水性极具重要意义。Ti6A14V合金和复合材料具有强度大、热性能好等优点,在航空、航天以及其他等相关领域都有非常重要的应用,然而,大多数钛合金和复合材料表面都不具有自清洁性(疏水性能)。因此,制备出疏水钛合金表面和复合材料表面,对拓展钛合金和复合材料在上述领域中的应用以及满足特殊应用需求具有重要意义。目前,超快激光技术,特别是飞秒激光微纳加工技术,具有超快时间分辨、超高峰值功率密度和超高聚焦能力三大特点,突破了材料和尺寸的限制,在制备微纳结构方面的应用前景广泛,有望成为解决制备钛合金和复合材料表面微结构的有效方式。针对以上需求及背景,本文采用飞秒激光微纳加工技术对钛合金和复合材料表面进行激光诱导、直写及低表面能修饰等加工处理,重点研究了飞秒激光参数对钛合金和复合材料表面微纳结构的变化规律的影响,系统表征了不同能量密度和脉冲个数等参数下的表面形貌,详细测试并分析了钛合金和复合材料的润湿性能,主要结论如下:(1)随着飞秒激光能量密度和脉冲个数变化,钛合金表面所产生的微结构总是经历着四个阶段,包括无激光诱导周期表面结构阶段、经典条纹结构阶段、经典与非经典条纹共存阶段、带有经典条纹结构的微驼峰结构阶段。(2)飞秒激光加工复合材料均可以在其表面制成了较为规整的菱柱或正方体阵列,菱柱边长为30μm～230μm不等,且每种角度(30°、60°、90° )参数下所加工得到菱柱的大小及其形状基本一致,但菱柱的形貌则会因能量密度、扫描间距和扫描次数的不同而有所变化。(3)研究表明,飞秒激光加工所得到的具有微纳米结构钛合金表面和与疏水涂层相结合的具有微米级菱柱的复合材料表面均获得了疏水性能,分别在能量密度为0.74J/cm2、脉冲个数为256、扫描间距为30μm以及能量密度为0.37J/cm2、脉冲个数为328、扫描间距为80μm所加工钛合金和复合材料表面接触角最大,分别为 148.55° 和 148.7°。(4)疏水涂层性能检测的研究结果表明,低表面能涂层具有较强的结合力,当其与微纳结构表面作用时可以很好地降低冰的附着力,而且其具有较好的耐煤油、耐水及耐热冲击等能力。
[Abstract]:Superhydrophobic surface is a surface with a contact angle of more than 150 掳and a rolling angle of less than 10 掳. The main factors of forming superhydrophobic surface are microstructure and low surface energy. Microstructures play an important role because of their specific physical or chemical properties, based on the relevant research results. It is very important to construct micro-nano structure on the surface of materials. Ti6A14V alloy and composites have the advantages of high strength and good thermal properties in aeronautical. Aerospace and other related areas have very important applications, however, most titanium alloys and composite surfaces do not have self-cleaning (hydrophobicity). The preparation of hydrophobic titanium alloy surface and composite surface is of great significance to expand the application of titanium alloy and composite materials in these fields and to meet the special application needs. At present, ultra-fast laser technology is very important. Especially the femtosecond laser micro-nano processing technology has three characteristics: ultra-fast time resolution, ultra-high peak power density and ultra-high focusing ability, breaking through the limitation of material and size. It is expected to be an effective way to prepare titanium alloy and composite surface microstructure. In this paper, femtosecond laser micromachining was used to process titanium alloy and composite surface, such as laser induced, direct writing and low surface energy modification. The effects of femtosecond laser parameters on the surface microstructures of titanium alloys and composites were studied. The surface morphology of titanium alloys and composites was systematically characterized under different parameters such as energy density and number of pulses. The wettability of titanium alloy and composite is measured and analyzed in detail. The main conclusions are as follows: 1) the energy density and pulse number of femtosecond laser changes. The microstructure of titanium alloy surface always goes through four stages, including the phase of laser-free periodic surface structure, the phase of classical stripe structure, and the phase of coexistence of classical and non-classical fringes. Femtosecond laser machining composites with classic stripe structure of micro-hump can be fabricated into regular rhombohedral or square arrays on their surfaces. The side length of the rhombohedral column varies from 30 渭 m to 230 渭 m, and the size and shape of the rhombohedral column are basically the same under the parameters of each angle of 30 掳~ 60 掳~ (90 掳). However, the morphology of the rhombohedral column varies with the energy density, scanning distance and scanning times. The hydrophobic properties of the microstructured titanium alloy and the composite surface with micron rhombohedral column were obtained by femtosecond laser processing. When the energy density is 0.74 J / cm ~ 2, the number of pulses is 256, the scanning distance is 30 渭 m, and the energy density is 0.37 J / cm ~ 2, the number of pulses is 328. The surface contact angle of titanium alloy and composite material with scanning distance of 80 渭 m is the largest, which is 148.55 掳and 148.7 掳. The low surface energy coating has strong adhesion, when it acts with the surface of micro-nano structure, it can reduce the adhesion of ice, and it has better resistance to kerosene, water and heat shock and so on.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN249

【参考文献】