航空铝合金LC4在酸性介质中的在线腐蚀监测  

In Situ Corrosion Monitoring of Aeronautic Aluminum Alloy LC4 in Acidic Medium

作　　者：孟琳[1] 何业东[1] 张巍[1] 姚红宇[2] 谢明立[2] 

机构地区：[1]北京科技大学北京市腐蚀磨蚀与表面技术重点实验室,北京100083 [2]中国民用航空总局航空安全技术中心,北京100028

出　　处：《航空材料学报》2007年第6期50-54,共5页Journal of Aeronautical Materials

基　　金：国家自然科学基金资助项目(批准号:60472114)

摘　　要：根据航空铝合金LC4进行阳极化和封孔处理后在不同浓度醋酸溶液中电容的变化进行在线腐蚀监测。阳极化铝合金LC4在醋酸溶液中的电容变化可分为三个阶段,缓慢增长期,快速增长期和大幅振荡期。结合SEM截面观察结果,在缓慢增长期,氧化膜致密耐蚀;在快速增长期,氧化膜变得疏松;大幅振荡期的出现标志着铝合金表面的阳极氧化膜已经被完全腐蚀掉。同时还研究溶液浓度和封孔对电容变化规律的影响。结果表明,可以通过阳极化铝合金LC4在醋酸溶液中的电容变化规律进行腐蚀状况的在线评价。另外,通过LCR数字电桥测得的阻抗-频率图谱与传统测量得到的电化学阻抗谱相比,在变化规律上具有较好的一致性。The capacitance measurement method was introduced, which could be used to monitor in situ the corrosion of aluminum alloy LC4 in CH3COOH solutions. The capacitance change of LC4 after anodizing in CH3COOH solutions could be divided three stages. During the slowly risng course of capacitance, the anodic film still maintained the uniformity and compactability; during the quickly rising course of capacitance, the anodic film became porous; and during the drastic oscillation course of capacitance, the anodic film had disappeared completely. In addition, the variation of impedance-frequency spectroscopy with the time measured by LCR number bridge was consistent with that of the EIS result.

关 键 词：在线腐蚀监测 电容变化 交流阻抗谱 封孔 

分 类 号：TG174[金属学及工艺—金属表面处理]