AlCl_(3)-[EMIM]Cl离子液体中铸铁表面电沉积耐蚀铝涂层研究  

Study on Electrochemical Depositing Al Anticorrosion Layer on Cast Iron Surface in AlCl_(3)-[EMIM]Cl Ion Liquid

作　　者：李园园 王锦霞[2] 谢宏伟 尹华意 宋秋实 LI Yuan-yuan;WANG Jin-xia;XIE Hong-wei;YIN Hua-yi;SONG Qiu-shi(School of metallurgy,Northeastern University,Shenyang 110819,China;College of Science,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]东北大学理学院,辽宁沈阳110819

出　　处：《材料保护》2022年第4期77-84,共8页Materials Protection

基　　金：国家自然科学基金青年项目(51504055);中央高校基本科研业务费资助项目(N172505002);国家青年人才计划和111工程(B16009)。

摘　　要：为了阐明铸铁表面耐腐蚀铝涂层的电化学沉积机理,在AlCl_(3)-[EMIM]Cl离子液体中,采用循环伏安法和计时电流法分别研究了铸铁表面铝电化学涂层沉积电极过程和形核生长机制。通过恒电流密度法电沉积制备铝涂层。利用交流阻抗、极化曲线和盐雾试验研究电流密度和沉积时间对沉积铝涂层铸铁耐蚀性能的影响。结果表明:铝在铸铁表面的析出过电位小,几乎为零;沉积受传质过程控制,形核符合三维瞬时成核机制;沉积铝涂层的铸铁自腐蚀电位较纯铸铁的负移、且腐蚀电流明显变小。沉积电流密度是影响铸铁耐腐蚀能力的决定性因素,电流密度增大,铸铁耐蚀性能提高,当电流密度达到30 mA/cm^(2)时,沉积铝涂层的铸铁腐蚀电流较铸铁基体降低了1个数量级。当沉积时间为20 min时,晶粒小且耐蚀性优良。For clarifying the electrochemical deposition mechanism of corrosion-resistant aluminum coating on surface of cast iron,the aluminum coating was electrodeposited on cast iron surface in AlCl_(3)-[EMIM]Cl ionic liquid,and the deposition electrode process and nucleation growth mechanism of aluminum electrochemical coating on surface of cast iron were studied by cyclic voltammetry and chronoamperometry.Subsequently,aluminum coating was prepared by constant current density electrodeposition,and the effect of the current density and deposited time on the corrosion resistance of cast iron deposited with aluminum coating was investigated by the AC impedance,polarization curve and salt spray test methods.Results showed that the precipitation overpotential of aluminum on the surface of cast iron was close to zero.The deposition was dominated by the mass transfer process,and the nucleation confirmed with three-dimensional instantaneous nucleation model.Comparing the cast iron sample,the self corrosion potential of the cast iron sample deposited aluminum coating shifted negatively,and the corrosion current also became smaller than that of cast iron.Moreover,the deposition current density was the decisive factor affecting the corrosion resistance of cast iron.With the increase of current density,the corrosion resistance of cast iron increased.The corrosion current value of the cast iron sample deposited aluminum coating under constant current density 30 mA/cm^(2) was lower one order than that of the cast iron substrate.The aluminum coating deposited for 20 min possessed small crystal grains and excellent corrosion resistance.

关 键 词：铸铁 铝涂层 AlCl_(3)-[EMIM]Cl离子液体 电极过程 腐蚀 电流密度 沉积时间 

分 类 号：TH117.1[机械工程—机械设计及理论]