不同淬火转移时间处理的7050-T6铝合金剥落腐蚀行为

来源期刊:中国有色金属学报(英文版)2014年第7期

论文作者:宋丰轩 张新明 刘胜胆 谈琦 李东锋

文章页码:2258 - 2265

关键词:7050-T76铝合金;厚板;剥落腐蚀;淬火转移时间;电化学

Key words:7050-T6 aluminum alloy; thick plate; exfoliation corrosion; quench transfer time; electrochemistry

摘    要:采用标准的剥落腐蚀浸蚀实验、剥落腐蚀后样品的强度损失测量以及电化学阻抗谱等技术,对固溶后经不同淬火转移时间处理的7050-T6态样品的剥落腐蚀行为进行研究。结果表明,7050-T6铝合金的抗剥落腐蚀性能随着淬火转移时间的延长而减小。背散射电子扫描连同透射电镜观察揭示,影响合金腐蚀性能的最主要因素是晶界的析出相覆盖率和析出相的微观组织,而晶界附近的贫溶质区对其不产生影响或影响较小。通过对合金进行静电势扫描发现,合金的剥落腐蚀敏感性与瞬态电势之间有很好的对应关系,即可以测试瞬态电势变化的数量来表征材料的剥蚀性能。

Abstract: The exfoliation corrosion (EFC) behavior of 7050-T6 aluminum alloy treated with various quench transfer time after solution heat treatment was investigated by standard EFC immersion tests, strength loss measurements after EFC tests and electrochemical impedance spectroscope (EIS) technique. The results showed that EFC resistance of the alloy decreased with increasing quench transfer time. Backscattered electron scanning electron microscope (SEM) together with transmission electron microscope (TEM) observations revealed that the coverage ratio and microstructure of precipitates at grain boundary area are the most important factors which influence the EFC susceptibility of the alloy, while precipitate-free zone (PFZ) near grain boundary has no or only a minor effect on it. In addition, galvanostatic measurements of the alloy present a good correlation between EFC resistance and transients in potential. The cumulated number of transients in potential can be used to evaluate EFC resistance of the alloy.

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号