摘要
针对液体战略导弹长期加注贮存工况下铝锂合金贮箱受推进剂腐蚀引发结构完整性退化的问题,开展了2195-T8铝锂合金在酸性介质中的腐蚀机理研究。通过全浸加速腐蚀试验结合扫描电镜(scanning electron microscopy,SEM)微观表征和能量色散谱(energy dispersive spectroscopy,EDS)分析技术,系统分析了铝锂合金在硝酸溶液中的动态腐蚀行为与微观析出相作用机制。结果表明:腐蚀初期以晶内亚稳态点蚀为主导,晶界电化学差异驱动腐蚀向纵深发展;θ′相与基体界面能差形成的非共格结构以及T1相周边贫Li区形成的电位梯度共同促进局部腐蚀扩展;β′/δ′强化相诱导的氧化膜结构缺陷能够显著增强腐蚀介质渗透动力学。
A study on the corrosion mechanism of 2195-T8 aluminum-lithium alloy in acidic media was conducted to address the issue of structural integrity degradation of aluminum-lithium alloy tanks caused by propellant corrosion under long-term liquid strategic missile fueling and storage conditions.The dynamic corrosion behavior and the interaction mechanism of micro-pre-cipitates of aluminum-lithium alloy in nitric acid solution were systematically analyzed through full immersion accelerated corrosion tests combined with scanning electron microscopy(SEM)micro-characterization and energy dispersive spectroscopy(EDS)techniques.The results show that in the initial stage of corrosion,intragranular metastable pitting corrosion is dominant,and the elec-trochemical difference at the grain boundaries drives the corrosion to develop in depth.The non-coherent structure formed by the interfacial energy difference between theθ′phase and the ma-trix,and the potential gradient formed in the Li-poor zone around the T1 phase jointly promote the local corrosion expansion.The structural defects of the oxide film induced by theβ′/δ′strengthening phase significantly enhance the penetration kinetics of the corrosive medium.
作者
田干
刘梦庆
刘德俊
王硕
赵一霖
寇光杰
杨新智
TIAN Gan;LIU Mengqing;LIU Dejun;WANG Shuo;ZHAO Yiin;KOU Guangjie;YANG Xinzhi(Rocket Force University of Engineering,Xi’an 710025,China)
出处
《火箭军工程大学学报》
2025年第4期68-75,共8页
Journal of Rocket Force University of Engineering
基金
国家自然科学基金(52272446)。
关键词
铝锂合金
硝酸腐蚀
晶间腐蚀
扫描电镜
能量色散谱
aluminum-lithium alloy
nitric acid corrosion
intergranular corrosion
scanning electron microscopy
energy dispersive spectroscopy
作者简介
第一作者:田干(1982-),男,副教授,主要从事铝锂合金腐蚀及疲劳断裂研究。E-mail:tiangan_2012@163.com;通信作者:刘德俊(1994-),男,讲师,主要从事铝锂合金腐蚀机理及演化规律研究。E-mail:liudjwxx801@yeah.net。
