切削液中的微生物对2219铝合金腐蚀行为影响  

Effect of Bacteria in the Metalworking Emulsions on Corrosion Behavior of 2219 Aluminum Alloys

作　　者：申媛媛 董耀华 杨懿 朱红玲 董丽华 SHEN Yuanyuan;DONG Yaohua;YANG Yi;ZHU Hongling;DONG Lihua(College of Ocean Science and Engineering,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]上海海事大学海洋科学与工程学院,上海201306

出　　处：《润滑与密封》2022年第4期11-21,共11页Lubrication Engineering

基　　金：上海深远海洋装备材料工程技术研究中心项目(19DZ2253100)。

摘　　要：为了研究切削液中滋生的微生物对航空航天用2219铝合金的腐蚀影响,采用失重法分析切削液中的微生物对2219铝合金的腐蚀速率,使用倒置荧光显微镜观察微生物在2219铝合金表面的附着情况,利用扫描电子显微镜(SEM)和白光干涉仪分别观察表面腐蚀产物形貌及腐蚀轮廓,并用能谱仪(EDS)分析表面腐蚀产物成分,最后利用电化学阻抗谱(EIS)研究该铝合金的腐蚀机制。结果表明:切削液中的微生物会附着在2219铝合金表面,形成不均匀的腐蚀产物膜和生物膜,微生物的存在使2219铝合金的腐蚀速率增大了59%;去除表面膜层后,发现明显的点蚀坑,最大深度为9.96μm。电化学结果还表明,在含有多种微生物的切削液中,铝合金的电荷转移电阻逐渐减低,腐蚀速率显著提高。研究表明,切削液中微生物的存在明显加速了2219铝合金的腐蚀,而且腐蚀形式以点蚀为主。To predict the effect of microorganisms breeding in cutting fluid on the corrosion of 2219 aluminum alloy(AA 2219)used in aerospace, the corrosion rate of microorganisms in cutting fluid on 2219 aluminum alloy was analyzed by weight loss method.The adhesion of microorganisms on the surface of 2219 aluminum alloy was observed by inverted fluorescent microscope.The corrosion morphology of products and the corrosion profile after removing corrosion products were observed by scanning electron microscope(SEM)and white light interferometer, respectively.The elements of surface corrosion products were analyzed by energy dispersive spectroscopy(EDS),and the corrosion mechanism was studied by electrochemical impedance spectroscopy(EIS).The results indicate that the microorganisms in the cutting fluid adhere to the surface of 2219 aluminum alloy to form uneven corrosion product film and biofilm.The presence of microorganisms increase the corrosion rate of 2219 aluminum alloy by 59%.After removing the surface film, obvious pitting pits are found, and the maximum depth is 9.96 μm.The electrochemical results also show that the charge transfer resistance of aluminum alloy immersed in cutting fluid with microorganisms decreases and the corrosion rate increases significantly.The microorganisms in the cutting fluid accelerate the corrosion of 2219 aluminum alloy obviously, and pitting corrosion is the main form of corrosion.

关 键 词：2219铝合金 微生物 切削液 点蚀 电化学阻抗谱 

分 类 号：TG172[金属学及工艺—金属表面处理]