摘要
环境障涂层(Environmental Barrier Coatings, EBCs)有望应用于新一代高推重比航空发动机热端部件。稀土焦硅酸盐,特别是Yb_(2)Si_(2)O_(7),被认为是性能优异的EBCs材料,但是服役条件下的钙镁铝硅酸盐(Calcium-Magnesium-Alumino-Silicate, CMAS)腐蚀成为限制其应用的瓶颈。CMAS组分对稀土硅酸盐涂层的腐蚀行为产生显著影响。采用真空等离子喷涂技术制备了Yb_(2)Si_(2)O_(7)涂层材料,研究了1 350℃空气环境中不同组分CMAS(Ca/Si=1.00、0.75、0.60)对Yb_(2)Si_(2)O_(7)涂层的腐蚀行为与机制。结果表明,CMAS成分对腐蚀行为有明显影响,经高Ca/Si比(1.00或0.75)的CMAS腐蚀后,Yb_(2)Si_(2)O_(7)涂层形成多孔的磷灰石相腐蚀层,腐蚀层下方存在磷灰石相和Yb_(2)Si_(2)O_(7)相的渗透层。经低Ca/Si比(0.60)的CMAS腐蚀后,涂层表面形成致密Yb_(2)Si_(2)O_(7)层,但不能有效阻止CMAS渗透,涂层内部形成渗透层。随腐蚀时间延长,渗透层厚度明显增大。
Environmental barrier coatings(EBCs)are expected to be applied to the hot-end components of new generation of highthrust-to-weight ratio aircraft engines.Rare-earth pyrosilicates,especially Yb_(2) Si_(2) O_(7),have been considered excellent EBCs materials.However,the corrosion of calcium-magnesium-aluminum-silicate(CMAS)under service conditions has become a bottleneck limiting their application.The CMAS component has a significant impact on the corrosion behaviors of rare-earth silicate coatings.Herein,Yb_(2)Si_(2)O_(7) coatings were prepared by vacuum plasma spraying technology,the corrosion behaviors and mechanisms of the coatings exposed to different CMAS components(Ca/Si=1.00,0.75,0.60)in air atmosphere at 1350℃were investigated.Results showed that the CMAS composition had a significant impact on the corrosion behaviors.After CMAS corrosion with high Ca/Si ratio(1.00 or 0.75),a porous apatite phase corrosion layer was formed on the Yb_(2)Si_(2)O_(7) coating.Beneath the corrosion layer,there existed an infiltration layer comprising both apatite phase and Yb_(2) Si_(2) O_(7) phase.After CMAS corrosion with low Ca/Si ratio(0.60),a dense Yb_(2) Si_(2) O_(7) layer was formed on the surface of the coating,but it failed to effectively prevent CMAS infiltration,resulting in the formation of an infiltration layer within the coating.As the corrosion time increased,the thickness of the infiltration layer grew significantly.
作者
张乐
钟鑫
王永胜
牛亚然
吕明达
ZHANG Le;ZHONG Xin;WANG Yongsheng;NIU Yaran;LYU Mingda(Science and Technology on Power Beam Processes Laboratory,AVIC Manufacturing Technology Institute,Beijing 100024,China;Aviation Key Laboratory of Science and Technology on Advanced Surface Engineering,Beijing 100024,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China)
出处
《材料保护》
2025年第10期10-19,共10页
Materials Protection
基金
稳定支持项目(KZ562501113)
国防基础科研计划(JCKY202213C007)。
