镁合金表面自清洁、耐高温复合膜层的制备与表征  

Preparation and Characterization of Self-cleaning and High-temperature-resistant Composite Coating on Magnesium Alloy

作　　者：周漪 胡淋 赵兴旺 邓杰文 ZHOU Yi;HU Lin;ZHAO Xing-wang;DENG Jie-wen(AVIC Chengdu Aircraft Industrial(Group)Co.,Ltd.,Chengdu 610091,China;Chongqing University,Chongqing 400044,China)

机构地区：[1]成都飞机工业(集团)有限责任公司,成都610091 [2]重庆大学,重庆400044

出　　处：《表面技术》2023年第5期298-305,共8页Surface Technology

基　　金：国家自然科学基金项目(21773019)。

摘　　要：目的 在镁合金表面制备自清洁、耐高温复合膜层,拓展镁合金在严酷环境中的应用。方法 采用化学转化-沸水封闭-硬脂酸修饰三步处理,在AZ31镁合金表面制备含有耐高温锆化合物组分的低黏附、超疏水复合膜层。利用场发射扫描电子显微镜(FESEM)表征膜层形貌。利用X射线光电子能谱仪(XPS)表征膜层成分。利用接触角测量仪(CA)和高速摄像机(HSC)表征膜层润湿性和黏附性。以粉笔灰为模拟污染物测试膜层在空气和油相中的自清洁性能。通过高温暴露试验和循环沸水浸泡试验测试膜层的耐高温性能。结果 复合膜层主要由锆/镁的(氢)氧化物及硬质酸盐组成,呈被部分填充的纳米纤维组成的微米网络结构。水在膜层表面的静态接触角为160.4°、滚动角为1°,符合“Cassie-Baxter”模型,膜层具有超疏水、低黏附特性;复合膜层具有优异的自清洁性能和耐高温性能。结论 成功制备了含有耐高温锆化合物组分的低黏附、超疏水复合膜层,该膜层具有自清洁、耐高温性能。The composite coatings with self-cleaning and high-temperature-resistant functions are indispensable for magnesium alloys to widen their application in harsh environments.In this paper,the composite coating that has superhydrophobic and low adhesive characteristics with self-cleaning and high-temperature-resistant functions was prepared on the AZ31 magnesium alloy surface by chemical conversion,boiling-water immersion and stearic-acid modification.The surface morphology of the coating was observed by field emission scanning electron microscopy(FESEM).The chemical composition of the coating was identified by X-ray photoelectron spectroscopy(XPS).The wettability and adhesion of the coating surface to water was evaluated by contact angle measuring instrument(CA)and high-speed camera(HSC).The self-cleaning function of the coating in air and oil(cyclohexane)was measured with chalk powders as the target contaminant.The hightemperature-resistant function of the coating was evaluated by the high-temperature exposure test and boiling-water immersion cycling test.The characterization results indicated that the as-prepared coating was composed of(HYDR)oxides and stearates of Zr and Mg,which presented as partly-filled micro-nets formed by nanofibers.The coating surface had a high static water contact angle of 160.4° and a low roll-off angle of 1°,which indicated that the coating accorded with Cassie-Baxter model and had superhydrophobic and low adhesive characteristics.The coating demonstrated remarkable self-cleaning function in air and oil,and attractive high-temperature-resistant function in air and water.The as-prepared self-cleaning and high-temperature-resistant composite coating in this work is expected to widen the application of magnesium alloys in harsh environments.

关 键 词：镁合金 复合膜层 超疏水 低黏附 自清洁 耐高温 

分 类 号：TG174.4[金属学及工艺—金属表面处理]