含点蚀2050-T8铝锂合金应力腐蚀开裂实验研究  

Experimental Investigation on Stress Corrosion Cracking of 2050-T8 Aluminum-Lithium Alloy with Pitting Corrosion

作　　者：王伟臣 雷乂舻 宋海鹏[1] 杜娟 WANG Weichen;LEI Yilu;SONG Haipeng;DU Juan(Sino-European Institute of Aviation Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学中欧航空工程师学院,天津300300

出　　处：《有色金属(中英文)》2025年第1期10-21,共12页Nonferrous Metals

基　　金：中央高校基本科研业务费重点项目(3122022102)。

摘　　要：开展含点蚀2050-T8铝锂合金的应力腐蚀实验研究,结合声发射,数字图像相关(DIC)、扫描电镜研究了不同工况下(含单蚀坑和不同间隔双蚀坑)铝锂合金的损伤演化及失效规律。结果表明:含点蚀铝锂合金应力腐蚀开裂过程可以分为三个阶段:试件表面的预活化阶段、应力腐蚀裂纹萌生阶段和应力腐蚀裂纹扩展阶段。与单蚀坑情况相比,双蚀坑试件裂纹扩展阶段缩短,归因于两个腐蚀坑产生裂纹的相互联合。基于人工神经网络的声发射损伤分类分析表明,与单蚀坑情况相比,双蚀坑试样应力腐蚀开裂过程中发生了更多腐蚀行为,归因于腐蚀面积的增大;双蚀坑试件机械连续信号数量明显更多且更快集中出现,表明产生了更多塑性变形。Stress corrosion of 2050-T8 aluminum-lithium alloy with pitting(pits at different distance)were investigated.Using acoustic emission,digital image correlation(DIC)and scanning electron microscopy,the damage evolution and failure patterns of aluminum-lithium alloy under various conditions(including single and varying spaced double pitting)were discussed.The experimental results indicate that the stress corrosion cracking process of pitted aluminum-lithium alloy can be divided into three stages:the pre-activation stage on the specimen surface,the initiation stage of stress corrosion cracks,and the propagation stage of stress corrosion cracks.Compared with the single pitting condition,the crack propagation stage in specimens with double pitting is shortened,which is attributed to the interaction and coalescence of cracks originating from two pits.The acoustic emission damage classification analysis based on artificial neural network shows that compared with the single pit,more corrosion occurs in the process of stress corrosion cracking of the sample with double pit,which is attributed to the increase of corrosion area.The number of mechanical continuous signals increases more rapidly,indicating that the specimens with double pits produced more plastic deformation.

关 键 词：航空铝锂合金 预腐蚀 数字图像相关 应力腐蚀 声发射 

分 类 号：O341[理学—固体力学]