应用于垃圾焚烧炉的抗高温氯腐蚀镍基电弧涂层研究

Corrosion Resistance for High Temperature Chlorine of Arc-Sprayed Ni-Based Coatings Applied in Waste Incineration Boilers

针对垃圾焚烧锅炉管道受热面遭受的高温氯腐蚀和冲刷磨损问题,通过高速电弧喷涂在该受热面制备了镍基合金C276涂层,通过改进的高速电弧喷枪和优化工艺使涂层具备超低孔隙率,同时兼具高硬度和高结合强度等力学性能。通过金相显微镜、扫描电镜及能谱仪分析了涂层的组织结构,通过极化曲线及熔融盐模拟腐蚀试验考察了其腐蚀行为。结果表明:相对20G钢,该C276电弧涂层具有优良的抗熔融盐离子电化学性能及抗高温氯腐蚀性能。通过截面腐蚀层形貌观察及元素面分布分析,探讨了C276涂层的抗高温氯腐蚀机理。

Concerning with the hot chlorine corrosion and erosive wear problems in waste incineration boilers, the hot corrosion behaviors as well as microstrncture of Ni-based C276 alloy coating deposited by means of high-velocity arc spraying were investigated. A highly dense, high - hardness and high- bonding-strength C276 coating was obtained through a re- designed high speed arc- spray nozzle and optimized processing parameters. The structure of the coatings was analyzed by metallographic microscope, SEM and EDS, and the corrosion behavior was studied by means of polarization analysis and simulated molten salt corrosion behaviors. Results showed that comparing with 20G steel, the C276 coating had better molten salt ionic electrochemical resistance and hot chlorine corrosion resistance. The corrosion mechanism was further analyzed by compafing the cross- sectional corrosion images and element map distribution.