摘要
目的通过含有硬脂酸添加剂的阳极氧化工艺,获得耐蚀性优异的镁合金阳极氧化膜。方法采用直流电源阳极氧化法,在含有2 g/L硬脂酸的碱性氧化液中进行阳极氧化。通过SEM、ImageJ软件和TT230测厚仪分析氧化膜的微观形貌和膜厚,通过FTIR、XPS和XRD分析膜层成分,通过电化学测试检测膜层的耐蚀性能。结果氧化液中添加硬脂酸后,制备的氧化膜层孔隙率降低,孔径减小,孔洞数量下降,厚度增大,致密度提高。膜层的自腐蚀电流密度为3.15×10^–7 A/cm^2,与未加硬脂酸制备的氧化膜相比,降低了2个数量级,耐蚀性显著提升。结论硬脂酸添加剂通过提升成膜电压,增强火花放电效应、表面活性剂作用,改变膜层成分等机制,提升膜层耐蚀性能。
The paper aims to obtain magnesium alloy anodized film of good corrosion resistance through the anodizing process of stearic acid additive.Anodization was carried out in alkaline oxidizing solution containing 2 g/L of stearic acid by the DC power anodization method.The microstructure and the thickness of the oxide film were analyzed with SEM,ImageJ software and TT230 thickness gauge;the film composition was analyzed by FTIR,XPS and XRD;the corrosion resistance of the film was detected by electrochemical test.The results showed that the porosity,pore size and number of pores of the oxide film prepared by this method were reduced,while the thickness and the density of the film layer were increased.The selfcorrosion current density of the film layer was reduced to 3.15×10–7 A/cm²,which was decreased by two magnitudes compared with the oxide film without stearic acid additive.The corrosion resistance of the film layer was improved significantly.The stearic acid additives can improve the corrosion resistance of the film by increasing the film formation voltage,enhancing the spark discharge effect,surfactant action and changing the composition of the film.
作者
张新宇
唐聿明
赵旭辉
左禹
ZHANG Xin-yu;TANG Yu-ming;ZHAO Xu-hui;ZUO Yu(Laboratory of Electrochemical Process and Technology for Materials,Beijing University of Chemical Technology,Beijing 100029,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2020年第2期220-226,共7页
Surface Technology
关键词
镁合金
阳极氧化
硬脂酸
耐蚀性
电化学
magnesium alloy
anodizing
stearic acid
corrosion resistance
electrochemistry
