摘要
采用超声速火焰喷涂在Super304H钢表面制备NiCrAlY涂层,研究了表面涂覆Na2SO4+K2SO4+Fe2O3盐膜的NiCrAlY涂层在650℃不同SO2含量模拟烟气环境中的热腐蚀行为。采用X射线衍射(XRD),扫描电镜(SEM)能谱仪(EDS)对该涂层及其高温腐蚀产物的成分、形貌进行了分析。结果表明:NiCrAlY涂层在含0.15%(质量分数)SO2的模拟烟气环境中表现出良好的耐蚀性,随着SO2含量的升高腐蚀加重,涂层表面腐蚀产物主要为NiCr2O4并含有少量Fe2O3;由于腐蚀介质通过涂层缺陷向内扩散,在涂层与基体界面生成了硫的富集腐蚀产物带。
NiCrAlY coating was prepared on Super304 Hsteel surface by high velocity oxygen fuel spray.The hot corrosion behavior of the prepared NiCrAlY coatings covered with Na2SO4 + K2SO4+Fe2O3 salt film was investigated in simulated flue gas with different content of SO2 at 650℃.The microstructure and composition of the coating and corrosion products were characterized by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD).The results show that the NiCrAlY coating exhibited good corrosion resistance in the simulated flue gas with 0.15%(mass fraction)SO2.The corrosion rate of the NiCrAlY coating was accelerated with increase of SO2 content.The corrosion products on the surface of NiCrAlY coating were mainly NiCr2O4 and contained a small amount of Fe2O3.Due to the corrosive medium diffused inward through coating defects,a sulfur-rich corrosion layer formed at the interface between coating and substrate.
作者
倪进飞
洪嘉
刘光明
李茂东
张民强
彭昱晨
NI Jinfei;HONG Jia;LIU Guangming;LI Maodong;ZHANG Minqiang;PENG Yuchen(Guangzhou Special Pressure Equipment Inspection and Research Institute, Guangzhou 510663, China;Schoolof Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, China;MaterialResearch Institute, Dongfang Boiler Group Co.? Ltd., Zigong 643001, China)
出处
《腐蚀与防护》
CAS
北大核心
2019年第8期578-583,共6页
Corrosion & Protection
