大气等离子喷涂Si/Mullite+BSAS/Yb_(2)Si_(2)O_(7)环境障涂层的制备与水氧腐蚀行为  

Preparation and water-oxygen corrosion behavior of Si/Mullite+BSAS/Yb_(2)Si_(2)O_(7)environmental barrier coating by atmospheric plasma spraying

作　　者：崔永静 郭孟秋 马玉洁 周邦阳 范尚武[2] 焦健 成来飞[2] CUI Yongjing;GUO Mengqiu;MA Yujie;ZHOU Bangyang;FAN Shangwu;JIAO Jian;CHENG Laifei(Key Laboratory of Advanced Corrosion and Protection for Aviation Materials,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;Science and Technology on Thermostructural Composite Materials Laboratory,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]中国航发北京航空材料研究院航空材料先进腐蚀与防护航空科技重点实验室,北京100095 [2]西北工业大学超高温结构复合材料重点实验室,西安710072

出　　处：《航空材料学报》2024年第4期37-45,共9页Journal of Aeronautical Materials

基　　金：两机基础科学中心项目(P2022-B-Ⅳ-003-001)。

摘　　要：以固相烧结法制备的Yb_(2)Si_(2)O_(7)粉体作为原材料,采用大气等离子喷涂工艺在SiC基体表面制备Si/Mullite+BSAS/Yb_(2)Si_(2)O_(7)三层结构环境障涂层。利用扫描电子显微镜、能谱仪、X射线衍射分析仪、纳米压痕试验机等设备研究涂层的显微组织、相结构和力学性能。结果表明:粉体材料由83%Yb_(2)Si_(2)O_(7)相和17%Yb_(2)SiO_(5)相(质量分数)组成,等离子喷涂获得的Yb_(2)Si_(2)O_(7)层孔隙率为(6.61±0.65)%,涂层结合强度达(22.82±3.55)MPa,涂层断裂韧度达(1.98±0.12)MPa·m1/2。此外,涂层1350℃条件下水氧耦合腐蚀测试结果显示Yb_(2)Si_(2)O_(7)单斜相含量先降低后提高,硅黏结层高温氧化形成的热生长氧化物SiO_(2)与Mullite+BSAS界面相容,未发现Mullite+BSAS与Yb_(2)Si_(2)O_(7)层互扩散现象,硅层的损耗是涂层使用寿命的主要限制环节。The Si/Mullite+BSAS/Yb_(2)Si_(2)O_(7)tri-layer environmental barrier coating was prepared on the surface of the SiC substrate by atmospheric plasma spraying using solid-state sintering Yb_(2)Si_(2)O_(7)feedstock.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS),X-ray diffraction analyzer(XRD)and nanoindentation testing machine etc were employed to study the microstructure,phase composition,and mechanical properties of the coating.The results indicate that the powder is composed of 83%Yb_(2)Si_(2)O_(7)phase and 17%Yb_(2)Si_(2)O_(7)phase,the porosity of the Yb_(2)Si_(2)O_(7)layer obtained by plasma spraying is(6.61±0.65)%,the bonding strength of the coating is(22.82±3.55)MPa and the fracture toughness of the coating is(1.98±0.12)MPa·m^(1/2).Furthermore,the water-oxygen corrosion test results of the coating at 1350℃show that the monoclinic phase contents of the Yb_(2)Si_(2)O_(7)phase decrease first and then increase.The thermally grown oxide SiO2 formed by high-temperature oxidation of the silicon bonding layer is compatible with Mullite+BSAS,and interdiffusion between Mullite+BSAS and Yb_(2)Si_(2)O_(7)layers isn’t detected.Deterioration of the silicon layer is a major limiting factor in the lifetime of the coating.

关 键 词：环境障涂层 等离子喷涂 碳化硅陶瓷基复合材料 Yb_(2)Si_(2)O_(7) 

分 类 号：V254.2[一般工业技术—材料科学与工程] TG174.442[航空宇航科学与技术—航空宇航制造工程]