海洋平台用S355钢表面电弧喷涂Al涂层组织及性能  

Microstructure and performance of Al coating on S355 steel surface used in offshore platform by arc spraying

作　　者：董学泉 孔德军[1,2] 王进春[1] 

机构地区：[1]常州大学机械工程学院,江苏常州213164 [2]江苏省材料表面科学与技术重点实验室常州大学,江苏常州213164

出　　处：《材料热处理学报》2015年第4期215-220,共6页Transactions of Materials and Heat Treatment

基　　金：江苏省科协首席专家(工程师)项目;中国学位与研究生教育学会研究课题(C1-2013Y07-051)

摘　　要：利用电弧喷涂工艺在S355钢表面进行了喷涂Al涂层,通过SEM、EDS、XRD对试样表面-界面进行了形貌、物相、面扫描和线扫描分析。用能谱面扫描观察了涂层表面化学元素分布状态,并结合界面的能谱面扫描和线扫描分析,讨论了涂层与基体的结合机理。采用质量分数为3.5%Na Cl溶液进行了电化学性能测试,检验了Al涂层的耐腐蚀性能。结果表明,电弧喷涂Al涂层在S355基体表面形成均匀、致密、结合良好的Al涂层,其物相为纯Al和α-(Al Fe),其中α-(Al Fe)出现在扩散层;Al和O元素在涂层表面形成富集区,形成致密氧化膜对Al涂层进行保护;Al元素在结合界面形成富集层,其原子浓度发生阶梯过渡变化,在扩散层中发生Fe-Al化合反应,形成冶金结合方式;Al涂层极化曲线发生正向移动,耐腐蚀性较好,对S355钢基体起到了保护作用。Al coating was prepared on the surface of S355 steel used in offshore platform by arc spraying,the morphology,elements distribution and phases of the coating and the interface were analyzed by XRD,SEM and EDS analysis. The bonding mechanism of coating and substrate was discussed. The electrochemical properties of Al coating in 3. 5%( mass fraction) Na Cl solution were tested,and its corrosion resistance was observed. The results show that the uniform,dense and good bonding Al coating is formed on the surface of S355 steel substrate by arc spraying. The coating consists of pure Al and α-( Al Fe) in the diffusion layer. Al and O elements enriched areas are observed on the coating surface,indicating the formation of aluminum oxide film to protect the Al coating. Al element enriched layer forms at the interface,and the Al atomic concentrations exhibit step changing,which shows the Fe-Al chemical reaction occurs in the diffusion layer to form the metallurgical bonding. The polarization curve of the Al coating shows the good corrosion resistance to protect S355 steel substrate.

关 键 词：S355钢 电弧喷涂Al涂层 表面-界面形貌 电化学腐蚀 

分 类 号：TG174.4[金属学及工艺—金属表面处理]