电流密度对电沉积CoCrNi中熵合金薄膜显微组织及耐蚀性的影响  

Effect of current density on microstructure and corrosion resistance of electrodeposited CoCrNi medium-entropy alloy film

作　　者：黄桢婧 黄峰[1] 袁玮[1] 胡骞[1] 卢献忠 HUANG Zhenjing;HUANG Feng;YUAN Wei;HU Qian;LU Xianzhong(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China;Shanghai Baosteel Casting Co.,Ltd.,Shanghai 201999,China)

机构地区：[1]武汉科技大学,省部共建耐火材料与冶金国家重点实验室,湖北武汉430081 [2]上海宝钢铸造有限公司,上海201999

出　　处：《电镀与涂饰》2024年第9期34-43,共10页Electroplating & Finishing

基　　金：国家自然科学基金(U21A20113);湖北省自然科学基金创新群体(2021CFA023)。

摘　　要：[目的]目前CoCrNi中熵合金的制备多采用粉末冶金、熔炼等工艺,存在操作繁琐、成本高等问题。电沉积技术不仅具有操作简单、成本低廉、能耗小等优点,还可通过改变工艺参数来调控薄膜的成分和组织结构。[方法]采用直流电沉积技术在铜基体上制备CoCrNi中熵合金薄膜。采用X射线衍射分析仪(XRD)、场发射电子探针扫描分析仪(FE-EPMA)和能谱仪(EDS)分析了不同电流密度下所得CoCrNi合金薄膜的晶相结构、形貌及元素分布,并通过电化学测量技术研究了电流密度对薄膜耐蚀性的影响。[结果]CoCrNi合金薄膜由球状颗粒及颗粒团簇组成,呈非晶态结构;薄膜中的Co、Cr和Ni元素都均匀分布。随电流密度增大,膜层中Co的质量分数先减小后趋于平缓,Cr的质量分数先增大再变平缓,Ni的质量分数则变化不大。随着Cr含量和显微硬度的增大,CoCrNi合金薄膜表面开始出现微裂纹,耐蚀性先变好后变差。[结论]电流密度对CoCrNi合金薄膜的耐蚀性有显著影响,在电流密度100 mA/cm^(2)下电沉积所得CoCrNi中熵合金薄膜虽然存在微裂纹,但其耐蚀性最佳。[Introduction]CoCrNi medium-entropy alloy is mostly prepared by powder metallurgy,melting,and other methods,which has the problems of cumbersome operation and high cost.Electrodeposition technology not only has the advantages of simple operation,low cost,and less energy consumption,but also allows the composition and organization of deposit to be regulated by changing the process parameters.[Method]CoCrNi medium-entropy alloy films were prepared on copper substrate by electrodeposition under direct current density.The phase structure,morphology,and element distribution of CoCrNi medium-entropy alloy films electrodeposited at different current densities were analyzed by X-ray diffraction(XRD),field-emission electron probe microanalysis(FE-EPMA),and energy-dispersive spectroscopy(EDS),respectively.The effect of current density on the corrosion resistance of CoCrNi alloy film was studied by electrochemical measurements.[Result]The electrodeposited CoCrNi alloy film consists of spherical particles and particle clusters with an amorphous structure.All of the elements i.e.Co,Cr,and Ni were uniformly distributed through the alloy film.With the increasing of current density,the mass fraction of Cr was initially increased and then stabilized,the mass fraction of Ni was decreased firstly and then stabilized,while the mass fraction of Ni was almost unchanged.With the increasing of Cr content,the microhardness of CoCrNi alloy film was increased,accompanied with the appearance of some microcracks,and its corrosion resistance get better initially and then worse.[Conclusion]Current density has great impact on the corrosion resistance of CoCrNi medium-entropy alloy film.The CoCrNi film electrodeposited at 100 mA/cm^(2) has the best corrosion resistance despite the presence of some microcracks.

关 键 词：直流电沉积 钴-铬-镍中熵合金薄膜 微观结构 耐蚀性 

分 类 号：TQ153.2[化学工程—电化学工业]