摘要
β-(Ni, Pt)Al相的Pt-Al涂层具有优异的抗氧化性能,常被用于航空发动机热端部件表面热防护。燃料燃烧产生的腐蚀产物复杂,会在部件表面形成复杂物相的熔盐沉积,因此明晰其腐蚀机制对提高β-(Ni, Pt)Al涂层的综合性能具有重要意义。除了针对单一组分Na_(2)SO_(4)熔盐热腐蚀行为的研究外,β-(Ni, Pt)Al涂层在Na_(2)SO_(4)+V_(2)O_(5)混合盐沉积下的腐蚀机制尚不明确。本工作通过在单相β-(Ni, Pt)Al涂层样品上分别涂覆Na_(2)SO_(4)和Na_(2)SO_(4)+V_(2)O_(5)的方式,对比研究了两种熔盐从950℃到室温循环条件下对涂层的腐蚀行为。通过对涂层腐蚀动力学、腐蚀产物物相演变和涂层形貌演变的分析发现:Na_(2)SO_(4)+V_(2)O_(5)混合盐的腐蚀表现出更大的氧化增重和更深的腐蚀深度。相比于单一Na_(2)SO_(4)腐蚀,V_(2)O_(5)的加入导致起始氧化膜发生酸性熔融,使其失去保护作用,并加快Pt从β-(Ni, Pt)Al相中析出,使涂层氧化抗性恶化。V_(2)O_(5)通过促使Na_(2)SO_(4)释放更多的SO_(3)来提高腐蚀界面处的硫化反应速率。本工作揭示了V_(2)O_(5)在熔盐热腐蚀中的作用机制,对如何提高β-(Ni, Pt)Al涂层的热腐蚀抗性具有重要指导意义。
Theβ-(Ni,Pt)Al coating has excellent oxidation resistance and is used for thermal protection of hot section components in advanced gas turbine engine during service.The fuel combustion products are complex and can form molten salt deposits on the surface of components.Clarifying its corrosion mechanism is of great significance for improving the comprehensive performance ofβ-(Ni,Pt)Al coatings.Except for the research on the hot corrosion behavior of single component Na_(2)SO_(4) molten salt,the corrosion mechanism ofβ-(Ni,Pt)Al coating under the deposition of Na_(2)SO_(4)+V_(2)O_(5) mixed salt is still unclear.This work prepared single-phaseβ-(Ni,Pt)Al coatings deposited by Na_(2)SO_(4) and Na_(2)SO_(4)+V_(2)O_(5),respectively,and compared their corrosion behaviors under thermal cycles from 950℃to room temperature.Through analysis of hot corrosion kinetics,phase evolution of corrosion products,and corrosion morphology evolution,it was found that the corrosion of Na_(2)SO_(4)+V_(2)O_(5) mixed salt exhibited greater oxidation weight gain and deeper corrosion depth.Compared to single Na_(2)SO_(4) corrosion,the V_(2)O_(5) leads to acidic melting of the initial oxide film,causing it to lose its protective effect.V_(2)O_(5) also accelerated the precipitation of Pt from theβ-(Ni,Pt)Al phase,which deteriorated the oxidation resistance of the coating.This work reveals the mechanism of V_(2)O_(5) accelerating hot corrosion,which has important guiding significance for improving the hot corrosion resistance ofβ-(Ni,Pt)Al coatings.
作者
叶利亚
陈宏飞
杨光
高彦峰
YE Liya;CHEN Hongfei;YANG Guang;GAO Yanfeng(Shanghai Space Appliance Co.,Ltd.,Shanghai 200331,China;School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China)
出处
《材料导报》
北大核心
2025年第7期172-175,共4页
Materials Reports
基金
国家自然科学基金(52072232)。
