工程科学学报，第41卷，第9期：1152-1161,2019年9月 Chinese Journal of Engineering,Vol.41,No.9:1152-1161,September 2019 DOI:10.13374/j.issn2095-9389.2019.09.006;http://journals.ustb.edu.cn S355海洋钢表面微弧氧化复合膜层耐蚀性能 贺 星12)，孔德军23)，宋仁国12) 1)常州大学材料科学与工程学院，常州2131642)常州大学江苏省材料表面科学与技术重点实验室，常州213164 3)常州大学机械工程学院，常州213164 区通信作者，E-mail:songrg(@hotmail.com 摘要采用激光熔覆与微弧氧化技术相结合在海洋钢表面制备了复合膜层.运用扫描电子显微镜(SEM)、能谱仪(EDS)和 X射线衍射仪(XD)表征复合膜层的微观结构，采用极化曲线、电化学阻抗谱、腐蚀磨损实验和浸泡腐蚀实验等测试方法研 究膜层在质量分数3.5%的NCl水溶液中腐蚀行为，并与熔覆涂层和基体进行对比.结果表明：复合膜层主要分为内致密层 和外疏松层，疏松层主要由y-AL,0,组成，致密层主要由a《-AL,0,组成，与基底层结合较好，复合膜层表面硬度最大能达到 HV。21423.3,比熔覆涂层高47.6%，其硬度较S355海洋钢有显著提升.基体在腐蚀和磨损交互作用中主要以腐蚀加速磨损 为主，涂层在交互作用中主要以磨损加速腐蚀为主，在经过微弧氧化处理后，膜层的自腐蚀电位负移，钝态电流密度上升，抗 磨蚀性能明显提高.熔覆涂层的浸泡腐蚀方式以点蚀为主，复合膜层腐蚀较轻微，阻抗模值最大能达到1033Ω℃m2,比熔覆层 提高两个数量级，这表明复合处理可进一步提高涂层的耐腐蚀性 关键词海洋钢：激光熔覆：微弧氧化：腐蚀 分类号TG174.44 Corrosion resistance of micro-arc oxidation composite coatings on S355 offshore steel HE Xing),KONG De-jun SONG Ren-gu 1)School of Materials Science and Engineering,Changzhou University,Changzhou 213164,China 2)Jiangsu Key Laboratory of Materials Surface Science and Technology,Changzhou University,Changzhou 213164,China 3)School of Mechanical Engineering.Changzhou University,Changzhou 213164,China Corresponding author:E-mail:songrg@hotmail.com ABSTRACT Composite coatings were prepared by laser cladding combined with micro-arc oxidation technique on the surface of $355 offshore steel,and the composite coating structures were analyzed using scanning electron microscopy,energy-dispersive spectroscopy, and X-ray diffraction.The corrosion behavior of the composite coating in 3.5%NaCl solution was investigated by polarization curve, electrochemical impedance spectroscopy,corrosive wear test,and immersion corrosion test,and compared with that of the cladding lay- er and substrate.The results show that the composite coating is mainly divided into inner dense layer and outer loose layer.The loose layer is mainly composed of y-Al2O3,and the dense layer is mainly composed of a-Al2O,and the surface hardness of the composite coating reaches the maximum value of HV.2 1423.3,which is 47.6%higher than that of the cladding coating.Moreover,the surface hardness of S355 offshore steel is significantly improved.The interaction between corrosion and wear in the substrate is mainly corro- sion-accelerating abrasion,whereas that in the coating is wear-accelerating corrosion.After micro-arc oxidation treatment,the corrosion potential of the composite coating moves negatively,the passive current density increases,the scale factor of wear-accelerated corrosion gradually decreases,and the corrosive wear resistance of the coating significantly improves.The immersion corrosion method of the cladding coating is mainly pitting corrosion,the composite coating is slightly corroded,and the maximum impedance modulus reaches 1033.cm2,which is two orders of magnitude higher than that of the cladding coating.This finding indicates that the corrosive wear 收稿日期：2018-08-14 基金项目：江苏省重点研发计划资助项目(BE2016052)工程科学学报,第 41 卷,第 9 期:1152鄄鄄1161,2019 年 9 月 Chinese Journal of Engineering, Vol. 41, No. 9: 1152鄄鄄1161, September 2019 DOI: 10. 13374 / j. issn2095鄄鄄9389. 2019. 09. 006; http: / / journals. ustb. edu. cn S355 海洋钢表面微弧氧化复合膜层耐蚀性能 贺 星1,2) , 孔德军2,3) , 宋仁国1,2) 苣 1)常州大学材料科学与工程学院, 常州 213164 2) 常州大学江苏省材料表面科学与技术重点实验室, 常州 213164 3)常州大学机械工程学院, 常州 213164 苣通信作者,E鄄mail:songrg@ hotmail. com 摘 要 采用激光熔覆与微弧氧化技术相结合在海洋钢表面制备了复合膜层. 运用扫描电子显微镜(SEM)、能谱仪(EDS)和 X 射线衍射仪(XRD)表征复合膜层的微观结构,采用极化曲线、电化学阻抗谱、腐蚀磨损实验和浸泡腐蚀实验等测试方法研 究膜层在质量分数 3郾 5% 的 NaCl 水溶液中腐蚀行为,并与熔覆涂层和基体进行对比. 结果表明:复合膜层主要分为内致密层 和外疏松层,疏松层主要由 酌鄄Al 2 O3 组成,致密层主要由 琢鄄Al 2 O3 组成,与基底层结合较好,复合膜层表面硬度最大能达到 HV0郾 2 1423郾 3,比熔覆涂层高 47郾 6% ,其硬度较 S355 海洋钢有显著提升. 基体在腐蚀和磨损交互作用中主要以腐蚀加速磨损 为主,涂层在交互作用中主要以磨损加速腐蚀为主,在经过微弧氧化处理后,膜层的自腐蚀电位负移,钝态电流密度上升,抗 磨蚀性能明显提高. 熔覆涂层的浸泡腐蚀方式以点蚀为主,复合膜层腐蚀较轻微,阻抗模值最大能达到10 5郾 3 赘·cm 2 ,比熔覆层 提高两个数量级,这表明复合处理可进一步提高涂层的耐腐蚀性. 关键词 海洋钢; 激光熔覆; 微弧氧化; 腐蚀 分类号 TG174郾 44 收稿日期: 2018鄄鄄08鄄鄄14 基金项目: 江苏省重点研发计划资助项目(BE2016052) Corrosion resistance of micro鄄arc oxidation composite coatings on S355 offshore steel HE Xing 1,2) , KONG De鄄jun 2,3) , SONG Ren鄄guo 1,2) 苣 1)School of Materials Science and Engineering, Changzhou University, Changzhou 213164, China 2)Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China 3)School of Mechanical Engineering, Changzhou University, Changzhou 213164, China 苣Corresponding author: E鄄mail: songrg@ hotmail. com ABSTRACT Composite coatings were prepared by laser cladding combined with micro鄄arc oxidation technique on the surface of S355 offshore steel, and the composite coating structures were analyzed using scanning electron microscopy, energy鄄dispersive spectroscopy, and X鄄ray diffraction. The corrosion behavior of the composite coating in 3郾 5% NaCl solution was investigated by polarization curve, electrochemical impedance spectroscopy, corrosive wear test, and immersion corrosion test, and compared with that of the cladding lay鄄 er and substrate. The results show that the composite coating is mainly divided into inner dense layer and outer loose layer. The loose layer is mainly composed of 酌鄄Al 2O3 , and the dense layer is mainly composed of 琢鄄Al 2O3 , and the surface hardness of the composite coating reaches the maximum value of HV0郾 2 1423郾 3, which is 47郾 6% higher than that of the cladding coating. Moreover, the surface hardness of S355 offshore steel is significantly improved. The interaction between corrosion and wear in the substrate is mainly corro鄄 sion鄄accelerating abrasion, whereas that in the coating is wear鄄accelerating corrosion. After micro鄄arc oxidation treatment, the corrosion potential of the composite coating moves negatively, the passive current density increases, the scale factor of wear鄄accelerated corrosion gradually decreases, and the corrosive wear resistance of the coating significantly improves. The immersion corrosion method of the cladding coating is mainly pitting corrosion, the composite coating is slightly corroded, and the maximum impedance modulus reaches 10 5郾 3 赘·cm 2 , which is two orders of magnitude higher than that of the cladding coating. This finding indicates that the corrosive wear