Investigation of the chemical composition of the thermally grown oxide layer in thermal barrier systems with NiCoCrAlY bond coats
Investigation of the chemical composition of the thermally grown oxide layer in thermal barrier systems with NiCoCrAlY bond coats
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研究具有 NiCoCrAlY 粘结层的热障系统中热生长氧化物层的化学成分
DOI：
10.1016/j.surfcoat.2006.02.024
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发表时间：
2006
影响因子：
5.4
通讯作者：
O. Fabrichnaya
中科院分区：
文献类型：
--
作者：
C. Mercer;S. Faulhaber;N. Yao;K. Mcilwrath;O. Fabrichnaya
通过扫描和透射电子显微镜、聚焦离子束切片和能量色散谱（EDS）元素绘图的组合，表征了具有NiCoCrAlY粘合层的隔热系统中热生长氧化物（TGO）层的形态和成分。研究揭示了一个复杂的TGO，表现出许多厚度不均匀性（“钉”），和纳米级的第二相颗粒的相当大的分布。这些颗粒已被确定为两种类型：夹带粘结涂层和氧化物的基础上Y2 O3和HfO 2的区域。氧化物的最可能的相组成是立方萤石的近似组成4 HfO 2-Y2 O3。Hf和Y从粘结层的扩散或在TGO生长期间粘结层元素的截留是形成这些氧化物颗粒的最可能的机制。
The morphology and composition of the thermally grown oxide (TGO) layer in a thermal barrier system with a NiCoCrAlY bond coat are characterized by a combination of scanning and transmission electron microscopy, focused ion beam sectioning and energy-dispersive spectroscopy (EDS) element mapping. The investigation has revealed a complex TGO that exhibits numerous thickness inhomogeneities (‘pegs’), and a sizable distribution of nano-scale second phase particles. These particles have been determined to be of two types: regions of entrained bond coat and oxides based on Y2O3and HfO2. The most probable phase makeup of the oxides is a cubic fluorite of approximate composition 4HfO2–Y2O3. Diffusion of Hf and Y from the bond coat or entrapment of bond coat elements during TGO growth are the most likely mechanisms for the formation of these oxide particles.