V_(2)O_(5)+Na_(2)SO_(4)熔盐作用下(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ热障涂层的热腐蚀行为研究  

Hot Corrosion Behavior of(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ Thermal Barrier Coatings Exposed to V_(2)O_(5)+Na_(2)SO_(4) Molten Salt

作　　者：郭磊[1,2] 辛会[1] GUO Lei;XIN Hui(School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China;Tianjin Key Laboratory of Advanced Joining Technology,Key Lab of Advanced Ceramics and Machining Technology of Ministry of Education,Tianjin 300072,China)

机构地区：[1]天津大学材料科学与工程学院,天津300072 [2]天津市现代连接技术重点实验室先进陶瓷与加工技术教育部重点实验室,天津300072

出　　处：《材料保护》2021年第2期1-8,共8页Materials Protection

基　　金：国家自然科学基金(51971156)资助。

摘　　要：为评估(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)涂层的耐熔盐腐蚀性能,用等离子喷涂法制备了(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ,研究了该涂层在V_(2)O_(5)+Na_(2)SO_(4)熔盐中的热腐蚀行为,将腐蚀条件为涂覆熔盐的涂层在700~1 000℃热处理2 h和10 h。结果表明:(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)涂层与V_(2)O_(5)+Na_(2)SO_(4)熔盐发生了明显的腐蚀反应,产物为GdVO4和t-ZrO22种,且腐蚀产物种类与热腐蚀温度和时间关系不大;但当腐蚀温度为700℃和800℃时,涂层表面有一定的Na2SO4残留。对腐蚀后涂层截面分析发现,涂层表面形成了反应层,该反应层可在一定程度上阻止熔盐渗透,但随着腐蚀温度的提升,形成反应层的能力变弱,涂层内可观察到较明显的熔盐痕迹;总体上来看,经700~1 000℃的熔盐腐蚀后,(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ涂层依然能保持结构完整性。根据路易斯酸碱规则提出了熔盐与(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)的反应机理,阐明了涂层抗熔盐腐蚀的机制。For evaluating the corrosion resistance of(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7) coating to molten salt,a(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ coating was prepared by air plasma spray.The hot corrosion behaviors of the coating in V_(2)O_(5)+Na_(2)SO_(4) molten salt at 700~1000℃for 2 h and 10 h were investigated.Results showed that the(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7) coating reacted obviously with V_(2)O_(5)+Na_(2)SO_(4) molten salt,and the corrosive products were Gd VO4 and t-ZrO2,which presented little relationship with hot corrosion temperature and time.When the corrosion temperature was 700℃or 800℃,there remained a certain content of Na2SO4 on the coating surface.From the cross-section analysis of coatings after corrosion,the coating surface formed a reactive layer that could suppress the permeation of molten salt to a certain degree.However,with the increase of the corrosion temperature,the ability to form the reaction layer became weak so that some obvious trace of molten salt could be observed in the coating.Generally,(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7)/YSZ coatings could still keep structure integrity after hot corrosion in the molten salt at 700~1000℃.Corresponding to the Lewis acid-base rule,the reaction mechanism between molten salt and(Gd_(0.9)Sc_(0.1))_(2)Zr_(2)O_(7) coating was proposed for clarifying the principle of the coating resisting to molten salt corrosion.

关 键 词：热障涂层 等离子喷涂 (Gd0.9Sc0.1)2Zr2O7 V2O5+Na2SO4 热腐蚀 

分 类 号：TG174.44[金属学及工艺—金属表面处理]