蒙皮涂层在地中海气候和热带沙漠气候过渡地区的腐蚀行为模拟

Corrosion Simulation of Aircraft Skin Coating under Transitional Mediterranean Climate and Tropical Desert Climate

目的再现地中海和热带沙漠过渡气候环境下飞机蒙皮涂层的腐蚀特征。方法采用单项试验、组合循环试验等方式对涂层试样开展模拟加速试验,观察涂层的腐蚀形态。采用扫描电镜和X射线光电子能谱分析技术研究样品表面的显微形貌及元素含量变化情况。结果盐雾试验、周期浸泡试验和湿热-盐雾-光老化组合循环试验中,样品均出现了起泡现象,这几种试验方法均强化了腐蚀介质Cl?的作用。盐雾试验和湿热-盐雾-光老化组合循环试验中的腐蚀形态与实际使用中出现的腐蚀现象基本一致。周期浸泡试验中,除起泡外,涂层还出现了实际使用过程中未出现的玷污现象。结论盐雾试验的模拟效率最高,蒙皮涂层出现起泡主要是当地大气和地下水中Cl?的作用。

Objective To reproduce corrosion characteristics of aircraft skin coating under transitional Mediterranean climate and tropical desert climate. Methods Simulative acceleration test was carried out on the coating samples through single test, combined cycle test, etc. to observer the corrosion characteristics of coating. The microstructure and element distribution of the surface were analyzed by ESEM and XPS. Results The bubble phenomenon appeared in salt fog test, cycle immersion test and damp heat-salt fog-solar radiation test, while the function of Cl^- was reinforced in these tests. The corrosion characteristics in salt fog test and damp heat-salt fog-solar radiation test was similar to the actual corrosion phenomenon. Besides bubble, contamination that has never appeared in actual use appeared in immersion test. Conclusion Salt fog test has the highest simulation efficiency. The bubble of the skin coating is mainly affected by Cl^- in local atmosphere and groundwater.