【摘要】：疏水表面因具有自清潔、減阻和抗磨性能,給人們生產(chǎn)生活帶來極大便利,為人類發(fā)展創(chuàng)造極大動力。微米結構,納米結構組成的多階結構和低表面能材料共同作用使得材料表面有疏水性。隨著微加工機理的研究,車削,銑削加工精度的提高,銑削刀具尺寸的逐漸縮小,用微切削方法加工出微米尺寸微結構研究其疏水性成為可能。表面接觸角是表征疏水性能的重要技術指標。為了研究微米尺寸微結構對水滴在其表面接觸角的影響,以Young氏方程,Wenzel方程及Cassie-Baxter方程為基礎,建立了二維情況下基于最小吉布斯自由能的接觸角預測模型,用微銑削的方法加工出微結構,并通過理論分析與切削試驗和接觸角測試相結合的方法探究微結構尺寸參數(shù)對接觸角的影響規(guī)律。首先,在光滑表面Young氏方程和粗糙表面Cassie-Baxter方程的基礎上,建立了二維情況下基于最小吉布斯自由能的接觸角預測模型,并且考慮斜壁對氣-液接觸線的影響對預測模型進行了修正。利用接觸角預測模型及其修正研究微結構材料和尺寸參數(shù)對接觸角的影響和疏水性微結構設計。研究結果表明,疏水性基底相對于親水性基底加工出的微結構有更大的接觸角提升趨勢。增大微結構間隙寬度,減小凸臺寬度,減小微結構斜壁角度,有利于接觸角的提升。其次,設計了直壁溝槽、方柱陣列、斜壁溝槽和斜壁陣列四種類型的微結構,通過微銑削方法加工出設計的微結構,并測量水滴在微結構表面的接觸角。最后,采用理論分析與試驗結合的方法研究不同幾何尺寸參數(shù)的直壁溝槽、方柱陣列、斜壁溝槽和斜壁陣列四種類型的微結構對水滴在其表面接觸角的影響。研究結果表明,溝槽與方柱陣列微結構可以使水滴在其表面的接觸角增大,接觸角隨著微結構間距增加而增大,隨著凸臺(方柱)寬度增大而減小。直壁溝槽微結構上水滴在垂直于溝槽方向和平行于溝槽方向的接觸角有差異并且相互影響；水滴在直壁溝槽微結構有著更穩(wěn)定的接觸角變化,而在方柱陣列微結構表面有更大的接觸角,并且更接近球狀。相對于直壁結構,斜壁結構的存在雖然會增加水滴在微結構表面的接觸角,但是增大了水滴在微結構表面的不穩(wěn)定性,水滴更容易進入微結構內部呈現(xiàn)出Wenzel狀態(tài)。此外,斜壁的存在使得微結構尺寸參數(shù)對接觸角的影響減小。
[Abstract]:Because of its self-cleaning, drag-reducing and anti-wear properties, hydrophobic surface brings great convenience to people's production and life, and creates great impetus for human development. The surface hydrophobicity of micro-structure, nano-structure and low surface energy materials can be obtained by the combination of multi-order structure and low surface energy material. With the study of micro-machining mechanism, the improvement of turning and milling precision, and the gradual reduction of milling tool size, it is possible to study the hydrophobicity of micro-size microstructure by micro-cutting method. Surface contact angle is an important technical index for characterizing hydrophobic properties. In order to study the effect of micro-structure on the contact angle of water droplets on its surface, based on Young equation, Wenzel equation and Cassie-Baxter equation, a two-dimensional contact angle prediction model based on minimum Gibbs free energy was established. The micro-structure was machined by micro-milling, and the influence of micro-structure size parameters on contact angle was investigated by combining theoretical analysis with cutting test and contact angle test. Firstly, based on the Young equation of smooth surface and the Cassie-Baxter equation of rough surface, the contact angle prediction model based on minimum Gibbs free energy in two-dimensional case is established. The prediction model is modified considering the influence of inclined wall on the gas-liquid contact line. The contact angle prediction model and its modification are used to study the influence of microstructure materials and size parameters on the contact angle and the hydrophobic microstructure design. The results show that the contact angle of hydrophobic substrate is higher than that of hydrophilic substrate. Increasing the width of the microstructure gap, reducing the width of the raised platform and decreasing the angle of the inclined wall of the microstructure are beneficial to the elevation of the contact angle. Secondly, four kinds of micro-structures are designed, which are straight-wall groove, square column array, oblique-wall groove and oblique-wall array. The micro-structure is machined by micro-milling method, and the contact angle of water droplets on the microstructure surface is measured. Finally, the effects of four types of microstructure, such as straight-wall grooves, square-column arrays, oblique-wall grooves and oblique-wall arrays, on the contact angle of water droplets on the surface of the droplets are studied by means of theoretical analysis and experiment. The results show that the micro-structure of groove and square column array can increase the contact angle of water droplets on its surface, and the contact angle increases with the increase of microstructure spacing, and decreases with the increase of the width of convex platform (square column). The contact angles of the droplets perpendicular to the grooves and parallel to the grooves are different and affect each other in the microstructure of the straight-walled grooves. Water droplets have a more stable contact angle on the straight-wall grooves and larger contact angles on the surface of the square-column array, and are closer to globules. Compared with the straight wall structure, the existence of oblique wall structure can increase the contact angle of water droplets on the microstructure surface, but increase the instability of water droplets on the microstructure surface. The water droplets are more likely to enter the microstructure inside the Wenzel state. In addition, the influence of microstructure size parameters on the contact angle is reduced due to the existence of inclined wall.
【學位授予單位】：山東大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TG54

【相似文獻】

相關期刊論文 前4條

1 麻沁甜;肖遠龍;童敏曼;李正杰;陽慶元;劉大歡;仲崇立;;熱力學和計算化學在納微結構材料構效關系研究與設計中的應用[J];中國科學:化學;2014年06期

2 程永來;用核化法制造毫微結構[J];高技術通訊;1994年10期

3 任淮輝;李旭東;李俊琛;;顆粒增強復合材料微結構的數(shù)值模擬與虛擬失效[J];機械工程學報;2010年04期

4 ;[J];;年期

相關會議論文 前2條

1 孟永鋼;吳昊;郭占社;蘇才鈞;;硅微結構材料的疲勞性能與摩擦學性能評價方法[A];慶祝中國力學學會成立50周年暨中國力學學會學術大會’2007論文摘要集（上）[C];2007年

2 那仁滿都拉;額爾敦倉;韓元春;;微結構固體中孤立波形成過程的數(shù)值模擬[A];力學與工程應用[C];2012年

相關重要報紙文章 前3條

1 本報記者 張曄;微結構世界里“看熱鬧”[N];科技日報;2005年

2 本報記者左常睿;探微析理 巧奪天工[N];科技日報;2002年

3 本報記者　　趙亞輝;“微”中見大[N];人民日報;2006年

相關博士學位論文 前3條

1 苗鳳娟;硅微結構材料的制備及應用[D];華東師范大學;2010年

2 王鐵強;不對稱微結構的構筑及其各向異性性質的研究[D];吉林大學;2013年

3 康明;基于亞波長金屬微結構的光場調控[D];南開大學;2012年

相關碩士學位論文 前4條

1 宋昊;疏水表面微結構設計與微銑削加工技術研究[D];山東大學;2015年

2 何雪梅;基于微結構的熱輻射特性控制研究[D];南京理工大學;2012年

3 龐小龍;二維微結構表面浸潤性研究[D];南京郵電大學;2013年

4 魏小龍;二維光學微結構光反射特性的研究及其在硅基太陽能電池中的應用[D];安徽大學;2015年

，

本文編號：2470580