封孔处理对PS45热喷涂涂层抗热腐蚀性能的影响  

Effect of Sealing Treatment on Hot Corrosion Behavior of Thermal Spraying Inconel PS45 Coating

作　　者：倪进飞 熊义 刘光明[2] 翟伟 董猛 田继红[2] 师超 NI Jinfei;XIONG Yi;LIU Guangming;ZHAI Wei;DONG Meng;TIAN Jihong;SHI Chao(Guangzhou Special Pressure Equipment Inspection and Research Institute,Guangzhou 510663,China;School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330063,China;Material Research Institute,Dongfang Boiler Group Co.,Ltd.,Zigong 643001,China)

机构地区：[1]广州特种承压设备检测研究院,广东广州510663 [2]南昌航空大学材料科学与工程学院,江西南昌330063 [3]东方锅炉股份有限公司材料研究所,四川自贡643001

出　　处：《热加工工艺》2023年第20期101-106,共6页Hot Working Technology

基　　金：国家自然科学基金项目(51961028);博士启动基金项目(EA201901056)。

摘　　要：采用超音速火焰喷涂在20钢表面制备PS45涂层。采用正硅酸乙酯为基料,Cr_(2)O_(3)、Al_(2)O_(3)、Zr O_(2)、CeO_(2)等氧化物为填料制备了封孔剂。采用封孔剂对PS45涂层进行封孔处理。研究了封孔和未封孔的PS45涂层试样表面涂覆75%Na_(2)SO_(4)+25%NaCl(质量百分比)盐膜在750℃下的热腐蚀行为。采用XRD、SEM、EDS对腐蚀产物成分、结构、形貌进行分析。结果表明:PS45涂层腐蚀过程中增重较明显,样品表面生成由Cr_(2)O_(3)、NiCr_(2)O_(4)、NiO组成的腐蚀产物层。而PS45封孔涂层腐蚀增重较未封孔涂层降低约1/2,腐蚀过程中生成的方英石和封孔层中的层片状CeO_(2)对熔盐腐蚀具有一定的阻挡作用,抑制了熔盐对涂层的腐蚀;同时封孔层/涂层界面生成的富Cr氧化层能进一步提高封孔涂层的耐腐蚀性。PS45 coating was prepared on 20 steel substrate by high velocity oxygen fuel spray deposition.The sealing agent was prepared with TEOS as the sealing agent base material and Cr_(2)O_(3),Al_(2)O_(3),ZrO_(2),CeO_(2)as fillers.Then,the sealing agent was used to seal the pores existing in the PS45 coating.The hot corrosion behavior of the PS45 coating with and without sealant was studied by coating a film of mixed salts 75%Na_(2)SO_(4)+25%NaCl(mass fraction)on sample surface and corrosion at 750℃.The composition,structure and morphologies of the corrosion products were investigated by XRD,SEM and EDS.The results show that the mass gain is obvious in the corrosion process for PS45 coating.The corrosion products on the sample surface are identified as Cr_(2)O_(3),NiCr_(2)O_(4)and NiO.However,the mass gain of PS45 sealant coating is about half of the mass gain of unsealant coating.The corrosion products of the cristobalite and layered CeO_(2)on the sample surface have a certain blocking effect for molten salt corrosion during the corrosion process.The Cr-rich oxide layer formed at interface of the sealing layer and PS45 coating can furtherly improve the corrosion resistance of the sealing layer.

关 键 词：PS45涂层 封孔层 热腐蚀 

分 类 号：TG178[金属学及工艺—金属表面处理]