阳极化对SP700钛合金/2A12铝合金偶对电偶腐蚀影响研究  

Effect of Anodizing on Couple Galvanic Corrosion of SP700 Titanium Alloy/2A12 Aluminum Alloy

作　　者：孟莉莉 樊伟杰 朱彦海 廖金华 杨文飞 MENG Li-li;FAN Wei-jie;ZHU Yan-hai;LIAO Jin-hua;YANG Wen-fei(China Aviation Manufacturing Technology Research Institute,Beijing 100024,China;Naval Aviation University Qingdao Campus,Shandong Qingdao 266041,China)

机构地区：[1]中国航空制造技术研究院,北京100024 [2]海军航空大学青岛校区,山东青岛266041

出　　处：《装备环境工程》2023年第8期37-44,共8页Equipment Environmental Engineering

摘　　要：目的研究阳极化处理对SP700钛合金与2A12铝合金电偶对的腐蚀行为和机理的影响。方法采用电化学极化曲线测试法对阳极氧化处理前后的SP700钛合金的耐蚀性能进行初步研究,并以此作为边界条件,采用有限元数值模拟的方法,对不同状态的SP700钛合金与2A12铝合金组成的偶对电偶腐蚀情况进行模拟计算。同时,开展电偶对的电偶腐蚀试验,对模拟结果进行验证。此外,通过对电偶腐蚀后的试件表面微观形貌进行表征,进一步分析不同电偶对的腐蚀规律差异。结果SP700钛合金阳极氧化前的自腐蚀电位为-283 mV,腐蚀电流密度为6.164×10^(-9)A/cm^(2);氧化后的自腐蚀电位为-270 mV,腐蚀电流密度为8.589×10^(-10)A/cm^(2)。SP700钛合金阳极氧化前与2A12铝合金的试验和仿真平均电偶电流密度分别为6.81、6.76μA/cm^(2);SP700钛合金阳极氧化后与2A12铝合金的试验和仿真平均电偶电流密度分别为2.58、2.54μA/cm^(2)。结论SP700钛合金表面阳极化处理可有效降低与铝合金之间电偶腐蚀的敏感性。The corrosion law and mechanism of anodizing on the couple composed of SP700 titanium alloy and 2A12 aluminum alloy was studied.The corrosion resistance of SP700 titanium alloy before and after anodizing was studied by means of electrochemical polarization curve test.Taking this as the boundary condition,the couple corrosion of SP700 titanium alloy and2A12 aluminum alloy in different states was simulated by finite element numerical simulation;At the same time,the galvanic corrosion test of couple pairs was carried out to verify the simulation results.In addition,through the characterization of the surface micro morphology of the specimens after galvanic corrosion,the differences of corrosion laws of different couples were further analyzed.The self-corrosion potential of SP700 titanium alloy before anodizing was-283 mV and the corrosion current density was 6.164×10^(-9)A/cm^(2).The self-corrosion potential after oxidation was-270 mV and the corrosion current density was8.589×10^(-10)A/cm^(2).The self-corrosion potential of SP700 titanium alloy after oxidation had little difference,indicating that the self-corrosion driving force had little change.However,the self-corrosion current density of SP700 titanium alloy after oxidation was one order of magnitude smaller than that of SP700 titanium alloy before oxidation,indicating that the corrosion rate of titanium alloy after oxidation was significantly reduced.Therefore,it could be predicted that the galvanic current density between SP700 titanium alloy and 2A12 aluminum alloy after oxidation would be lower than that between SP700 titanium alloy and 2A12 aluminum alloy before oxidation.The formation of oxide film may reduce the galvanic corrosion rate between the two alloys and would be verified by galvanic corrosion simulation and galvanic corrosion test.The test and simulation average galvanic current densities of SP700 titanium alloy and 2A12 aluminum alloy before anodizing were 6.81μA/cm^(2) and 6.76μA/cm^(2),respectively.The error between the test current dens

关 键 词：SP700钛合金 2A12铝合金 极化 电偶腐蚀 阳极氧化膜 数值模拟仿真 

分 类 号：TG172[金属学及工艺—金属表面处理]