本文選題：粘附強度　切入點：化學刻蝕　出處：《廣州大學》2014年碩士論文　論文類型：學位論文

【摘要】：表面結冰不但降低了制冷系統(tǒng)的運行效率，而且給航天航空、電力傳輸、網絡通訊等領域的正常運行帶來了潛在的危險，甚至會造成嚴重的經濟損失。因此，研究材料表面冰層粘附特性，特別是研究不同表面冰粘附強度的變化規(guī)律對抑冰除冰、保證系統(tǒng)安全高效運行有著重要意義。 采用NaOH溶液化學刻蝕、氟硅烷修飾裸鋁表面等方法制備了實驗所需的具有不同表面特性的試片，并對其表面特性進行了實驗表征，將各試片置于低溫條件下結冰，利用構建的冰粘附強度實驗裝置，測試浸潤性、表面微觀結構和表面能等對試片表面冰粘附強度的影響規(guī)律，，進而探索抑冰減粘的材料表面，從而指導低粘附表面結構的優(yōu)化設計。 結果顯示，疏水表面粘附強度均小于親水表面的粘附強度，其中刻蝕時間為8min，氟硅烷修飾24h的S8#試片，表面接觸角值最大（154.9°），其冰粘附強度最小，僅為22.8kPa，相比裸鋁試片，冰粘附減小系數達3.3。進一步的研究表明冰粘附強度與接觸角兩者之間關系并不明確，不能單純用表面接觸角來評價材料表面抑冰減粘性能。 通過對冰粘附強度與表面粗糙度、分形維數關系的分析，發(fā)現(xiàn)親水表面冰粘附強度隨著粗糙度的增加而增加，疏水表面上冰粘附強度隨著粗糙度的增加而減小，這主要是由于表面粗糙度對浸潤性的不同影響造成的。進一步分析表明，表面粗糙度與其粘附強度存在下列關系y=1.0726x+52.509（親水）， y-0.6736x+74.483（疏水）；此外，親水表面冰粘附強度隨分形維數的增加而減小，疏水表面冰粘附強度隨分形維數的增加而增加。相應的線性關系式分別為： y=-146.6x+493.5（親水）， y=95.45x-209.9（疏水）。 表面能也對冰粘附強度有較大影響。表面能較小的試片，冰粘附強度也較小；表面能較大的試片，冰粘附強度也較大。從經典異質核化理論分析，經氟硅烷修飾后表面能較低的鋁表面，臨界冰晶核半徑較大，冰晶較難形成，導致冰粘附強度較小。
[Abstract]:Surface icing not only reduces the operational efficiency of the refrigeration system, but also brings potential danger to the normal operation of aerospace, electric power transmission, network communication and other fields, and even causes serious economic losses. It is of great significance to study the adhesion characteristics of ice layer on the surface of materials, especially to study the change of ice adhesion strength on different surfaces to suppress ice and deicing, and to ensure the safe and efficient operation of the system. Samples with different surface properties were prepared by chemical etching of NaOH solution and modification of bare aluminum surface by fluorosilane. The surface properties of the specimens were characterized by experiments, and each specimen was frozen at low temperature. The effects of wettability, surface microstructure and surface energy on the ice adhesion strength on the surface of the test piece were tested by using the ice adhesion strength experimental device, and then the surface of the material which inhibited the ice adhesion was explored. Therefore, the optimum design of low adhesion surface structure can be guided. The results showed that the adhesion strength of hydrophobic surface was lower than that of hydrophilic surface. The surface contact angle of S8# specimen modified with fluorosilane for 24 hours was 154.9 擄/ m, and the adhesion strength of ice was the smallest, only 22.8kPa. compared with bare aluminum specimen, the adhesive strength of hydrophobic surface was lower than that of hydrophilic surface. Further research shows that the relationship between the ice adhesion strength and the contact angle is not clear, and the surface contact angle can not be used to evaluate the surface ice antiadhesion performance of the materials. Through the analysis of the relationship between ice adhesion strength and surface roughness and fractal dimension, it is found that the ice adhesion strength of hydrophilic surface increases with the increase of roughness, and the ice adhesion strength on hydrophobic surface decreases with the increase of roughness. This is mainly due to the different effects of surface roughness on wettability. Further analysis shows that the relationship between surface roughness and its adhesion strength is as follows: y = 1.0726x 52.509 (hydrophilic, y-0.6736x 74.483) (hydrophobic; The adhesion strength of hydrophilic surface ice decreases with the increase of fractal dimension, and the adhesion strength of hydrophobic surface ice increases with the increase of fractal dimension. The corresponding linear relations are as follows: Y-146.6x 493.5 (hydrophilic, 95.45x-209.9). The surface energy also has a great influence on the ice adhesion strength. The ice adhesion strength is also smaller for the specimen with lower surface energy, and the ice adhesion strength is larger for the specimen with higher surface energy. When the surface energy of aluminum modified by fluorosilane is lower, the critical ice core radius is larger, and the ice crystal is difficult to form, which leads to the smaller adhesion strength of ice.
【學位授予單位】：廣州大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TB657

【參考文獻】

相關期刊論文 前2條

1 馮杰;盧津強;秦兆倩;;超疏水表面抗結冰性能研究進展[J];材料研究學報;2012年04期

2 朱定一;張遠超;戴品強;羅曉斌;;潤濕性表征體系及液固界面張力計算的新方法(Ⅱ)[J];科學技術與工程;2007年13期

本文編號：1578359