CeO_(2)颗粒对7075铝合金微弧氧化膜生长行为及耐磨/耐蚀性能的影响  

Effect of CeO_(2)Particles on Growth Behavior and Wear/Corrosion Resistance of Micro-arc Oxidation Coating on 7075 Aluminum Alloy

作　　者：詹中伟 张骐 刘小辉 王帅星[2] 庞志伟 孙志华 葛玉麟 王琪超 杜楠[2] ZHAN Zhongwei;ZHANG Qi;LIU Xiaohui;WANG Shuaixing;PANG Zhiwei;SUN Zhihua;GE Yulin;WANG Qichao;DU Nan(Aviation Key Laboratory of Science and Technology on advanced Corrosion and Protection for Aviation Material,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330063,China;AECC Xi'an Power Control Technology Corporation,Xi'an 710077,China)

机构地区：[1]中国航发北京航空材料研究院航空材料先进腐蚀与防护航空科技重点实验室,北京100095 [2]南昌航空大学材料科学与工程学院,南昌330063 [3]中国航发西安航空动力控制科技有限公司,西安710077

出　　处：《表面技术》2024年第17期71-82,共12页Surface Technology

基　　金：国家自然科学基金(52261019);江西省主要学科学术和技术带头人培养计划(20204BCJL23033)。

摘　　要：目的通过CeO_(2)颗粒复合,进一步改善铝合金微弧氧化膜的耐磨和耐蚀性能。方法在硅酸盐-磷酸盐电解液体系中加入CeO_(2)颗粒,利用微弧氧化技术在7075-T6铝合金表面制备CeO_(2)颗粒复合氧化膜;从氧化电压、放电行为及膜层厚度的变化规律探讨CeO_(2)颗粒含量对微弧氧化膜生长过程的影响;通过扫描电子显微镜、动电位极化曲线、球-盘磨损试验等研究电解液中CeO_(2)颗粒浓度对微弧氧化膜微观结构、耐磨性能和耐蚀性能的影响。结果通过CeO_(2)颗粒的复合,改变了铝合金微弧氧化成膜过程的能耗分布,加速了微弧氧化膜的放电击穿。CeO_(2)颗粒复合会使膜层的生长速率有所下降,但氧化膜的致密性、均匀性及膜基的结合强度得到明显改善。CeO_(2)颗粒主要以熔融和嵌合等方式存在于氧化膜中。相较于普通微弧氧化膜,复合膜的摩擦因数普遍降低了约0.2,比磨损率也更低,耐磨性更佳。此外,复合膜呈现出更好的耐腐蚀性,其自腐蚀电流密度至少下降了50%,且在模拟海水中浸泡2000 h后腐蚀增重更小、腐蚀更轻微。在电解液中加入10 g/L的CeO_(2)颗粒时,所得复合膜的综合性能较佳。结论CeO_(2)颗粒复合以熔融或嵌合的方式沉积到铝合金微弧氧化膜中,有效减少了膜层的微孔等缺陷,提高了膜层的致密性和硬度,改善了膜层的耐蚀性和耐磨性。In order to further improve the wear resistance and corrosion resistance of micro-arc oxidation(MAO)coatings on the 7075-T6 aluminum alloy,CeO_(2)particles are added to silicate and phosphate a mixed electrolyte system for composite oxidation.The influence of CeO_(2)particle content on the growth process of MAO coatings is explored from the change laws in oxidation voltage,discharge behavior and film thickness.The surface microstructure,cross-sectional microstructure,and element distribution of MAO coatings prepared in electrolytes with different content of CeO_(2)particles are analyzed by scanning electron microscopy(SEM),and energy dispersive spectroscopy(EDS).The corrosion resistance and wear resistance of different coatings are analyzed through potentiodynamic polarization curves,electrochemical impedance spectroscopy,simulated immersion corrosion tests,and ball disc wear tests.The corrosion and wear mechanisms of MAO/CeO_(2)composite coatings are also analyzed.The results show that the composite of CeO_(2)particles changes the energy consumption distribution of the coating-forming process of MAO coatings for 7075 aluminum alloy,accelerates the discharge breakdown and increases the termination voltage of the oxidation process.The total energy consumption of preparing MAO/CeO_(2)composite coatings is about 60-120 kJ higher than that of preparing ordinary coatings.The addition of CeO_(2)particles reduces the growth rate of MAO coatings,but is helpful to improve the compactness and bonding strength of MAO coatings.The density of MAO/CeO_(2)composite coatings is about 5%-20%higher than that of ordinary MAO coatings of equivalent thickness.The critical load when the composite film ruptures is also increased by 1-3 N compared with ordinary oxide coatings.Besides,the microhardness of MAO coatings increases with the increase of the CeO_(2)particle content in the electrolyte.The CeO_(2)particles mainly enter into the MAO coatings by melting or embedding.CeO_(2)particles are mainly melt in the coating in a molten state

关 键 词：7075-T6铝合金 微弧氧化 CeO_(2)颗粒 硬度 耐磨性 耐蚀性 

分 类 号：TG178[金属学及工艺—金属表面处理]