应力载荷作用下5A06铝合金薄板材料在盐水中腐蚀行为  

Corrosion Behaviors of 5A06 Aluminum Alloy Sheet Under Stress Loading in Brine Solution

作　　者：马慧媛[1] 刘慧丛[1] 石文静[2] 施丽铭[2] 李卫平[1] 朱立群[1] MA Hui-yuan;LIU Hui-cong;SHI Wen-jing;SHI Li-ming;LI Wei-ping;ZHU Li-qun(School of Materials Science and Engineering,Beihang University, Beijing 100191,China;Beijing Institute of Spacecraft SystemEngineering,Beijing 100094,China)

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100191 [2]北京空间飞行器总体设计部,北京100094

出　　处：《材料工程》2018年第9期152-159,共8页Journal of Materials Engineering

基　　金：国家自然科学基金(51401011)

摘　　要：以铝合金薄板在受载及盐水作用下可能存在的腐蚀加速问题为研究背景,用两点弯曲法探讨1.8mm厚5A06铝合金薄板在50℃的3.5%NaCl溶液中的腐蚀行为,研究发现施加载荷可以促进铝合金薄板材料的腐蚀。对不同腐蚀时期的裂纹形貌、金相组织以及元素成分等进行分析发现:在盐水环境中应力载荷对材料腐蚀的促进体现在与腐蚀程度成正比的关系,受铝合金材料内固溶强化相的影响,材料阳极区优先溶解,形成点蚀坑;另外,应力载荷会导致铝合金薄板表面氧化膜撕裂,并促使腐蚀裂纹扩展。Based on the problem of corrosion acceleration possibly existing in aluminum alloy sheets under the influence of both loading and brine solution,the corrosion behavior of 5A06 aluminum alloy sheets with the thickness of 1.8mm by the two-point bending method in 3.5%NaCl aqueous solution at 50℃was discussed.It is found that stress actually can promote the speed of corrosion in these aluminum alloy sheets.Crack morphologies,metallurgical structures and elemental compositions in different corrosion periods of these samples were analyzed.The results show:firstly,large stress will cause severe corrosion,which proves that stress can accelerate the corrosion;secondly,the solid solution strengthening phase in aluminum alloy can cause the anode areas preferentially dissolve,resulting in the formation of corrosion pits.Furthermore,stress can result in tearing of oxide film on the aluminum alloy surface,and facilitate corrosion crack propagation.

关 键 词：5A06铝合金薄板 应力载荷 盐水 两点弯曲 腐蚀行为 

分 类 号：TG172.5[金属学及工艺—金属表面处理]