Microstructural features of mechanical failure in thermal barrier coating systems under static loadings†
Microstructural features of mechanical failure in thermal barrier coating systems under static loadings†
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静态载荷下热障涂层系统机械故障的微观结构特征†
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
Y. Harada
中科院分区：
文献类型：
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作者：
S. Takahashi;M. Yoshiba;Y. Harada
为了从微观结构的角度定性和定量地阐明等离子喷涂热障涂层（TBC）系统的失效机理，作为最基本的方面，利用光学显微镜对TBC系统在室温静载荷下的力学失效行为进行了原位观察。采用不同的陶瓷涂层材料制备了几种TBC体系。采用四点弯曲试验方法，对TBC试样的板形逐渐施加机械拉伸载荷或压缩载荷。结果表明，热障涂层的拉伸破坏行为与等离子喷涂后的表面涂层组织和热处理工艺密切相关。压缩破坏也是偶然发生的，并取决于界面区域的面漆强度。在不同的TBC体系中，具有精细分段的顶涂层的那些表现出良好的抗剥落性。
Abstract In order to clarify qualitatively and quantitatively the failure mechanism of plasma-sprayed thermal barrier coating (TBC) systems from the microstructural viewpoint, in situ observation of the mechanical failure behavior was conducted for TBC systems under the static loadings at ambient temperature; as the most fundamental aspect, by means of an optical microscopy. Several kinds of TBC systems were prepared by using different sorts of ceramic coating materials. Mechanical tensile loading or compressive loading was gradually applied to the plate shape of TBC specimen using a four-point bending test methodology. It was found that the tensile failure behavior of TBC systems depends strongly on the top-coat microstructures as well as heat treatment after the plasma spraying. The compressive failures were also found rather incidental and depended on the strength of top-coat at the interfacial region. Among different TBC systems, those with the finely segmented top-coat exhibited a good spalling resistance.