铌合金表面Cr_(2)O_(3)/MoSi_(2)/CoNiCrAlY复合涂层抗熔盐腐蚀性能研究  

Corrosion Resistance of Cr_(2)O_(3)/MoSi_(2)/CoNiCrAlY Composite Coatings on Niobium Alloy Surface to Molten Salt Corrosion

作　　者：方向青 孙乐 房文杰 李君豪 武子默 FANG Xiang-qing;SUN Le;FANG Wen-jie;LI Jun-hao;WU Zi-mo(School of Energy and Architecture,Xi′an Aeronautical Institute,Xi′an 710077,China;School of Materials Engineering,Xi′an Aeronautical Institute,Xi′an 710077,China)

机构地区：[1]西安航空学院能源与建筑学院,西安710077 [2]西安航空学院材料工程学院,西安710077

出　　处：《西安航空学院学报》2022年第5期58-64,共7页Journal of Xi’an Aeronautical Institute

基　　金：陕西省自然科学基础研究计划一般项目(2021JQ-853,2021JQ-849);陕西省教育厅专项科研计划项目(20JK0694);省级大学生创新创业训练计划项目(S202211736047)。

摘　　要：采用超音速大气等离子喷涂技术,在铌合金基体上制备Cr_(2)O_(3)/MoSi_(2)/CoNiCrAlY复合涂层,在1000℃下进行Na_(2)SO_(4)熔盐腐蚀性能测试实验,对涂层腐蚀前后的物相、表面形貌和微观组织进行分析,并对涂层的熔盐腐蚀机理进行解释。结果表明:喷涂态复合涂层层间结合紧密,其中Cr_(2)O_(3)阻挡层组织致密,喷涂过程中颗粒完全熔化,形成的阻挡层有少量孔洞;循环腐蚀200 min后,Cr_(2)O_(3)阻挡层表面生成颗粒状腐蚀产物Na_(2)CrO_(4),残留网络状Na_(2)SO_(4)。腐蚀后涂层内未发现熔盐渗入,无明显裂纹,涂层失重仅为1.28 mg/cm^(2),抗熔盐腐蚀性能良好。The Cr_(2)O_(3)/MoSi_(2)/CoNiCrAlY composites coating is prepared on niobium alloy substrate by supersonic atmospheric plasma spraying technology.The hot corrosion properties of the composites coating are tested at 1000℃ by Na_(2)SO_(4) molten salt.The phase,surface morphology and microstructure of the coating before and after corrosion are analyzed,and the mechanism of molten salt corrosion of the coating is explained.The results show that coating layers are closely bonded,and the Cr_(2)O_(3) barrier layer has dense microstructure.The particles melt completely during the spraying process,and there are a few holes in the barrier layer.After 200 minutes′cyclic corrosion,corrosion product granular Na_(2)CrO_(4) and network Na_(2)SO_(4) remain on the surface of Cr_(2)O_(3) barrier layer,and molten Na2SO4 remains as network.After corrosion,no molten salt infiltration is found in the coating,no obvious cracks are found,the weight loss of the coating is only 1.28 mg/cm^(2),and it proves an excellent corrosion resistance against molten salt.

关 键 词：熔盐腐蚀 Cr_(2)O_(3)涂层 等离子喷涂 铌合金 

分 类 号：TG174[金属学及工艺—金属表面处理] TB333[金属学及工艺—金属学]