热震过程中热障涂层隔热层内部裂纹扩展动态行为研究

项目名称： 热震过程中热障涂层隔热层内部裂纹扩展动态行为研究

项目编号： No.51202277

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 王亮

作者单位： 中国科学院上海硅酸盐研究所

项目金额： 25万元

中文摘要： 深入研究热障涂层的高温失效机制对于热障涂层寿命的评估及预测具有十分重要的意义。通过对裂纹扩展动态行为的研究有助于实现对涂层失效过程的实时跟踪，进一步深入理解涂层高温失效的过程。本项目拟通过等离子喷涂工艺制备双陶瓷层La2Zr2O7(LZ)/8YSZ、 纳米结构8YSZ、传统结构8YSZ三种涂层。采用加热-淬水法测试三种涂层的高温抗热震性能，并结合扩展有限元方法研究三种涂层隔热层内部裂纹在热震过程中扩展的动态行为，利用扫描电镜和声发射器研究裂纹在高温热震过程中的扩展规律以验证模拟结果。研究结果将建立不同热震温度下三种涂层隔热层的内部裂纹扩展的动态图像，揭示关键裂纹在热震过程中扩展形态及断裂参数的变化规律，深入探讨三种涂层的高温热震破坏形式及失效机制。本研究将为热障涂层的高温服役寿命预测奠定理论基础，并进一步为拓展高性能热障涂层在航空、航天及国防领域的应用提供科学依据。

中文关键词： 热障涂层；高温热震；裂纹扩展；模拟计算；声发射

英文摘要： To investigate the high temperature failure mechanism of the thermal barrier coatings (TBCs) in depth is of great significance for the life assessment and prediction of the TBCs. It is beneficial to realize the tracking of the failure of the coating in time and further understand the process of the high temperature failure of the coating in depth through the study of the dynamic behavior of crack propagation. Three kinds of TBCs (double ceramic layer La2Zr2O7/8YSZ, nanostructured 8YSZ TBCs and conventional 8YSZ TBCs) will be prepared by plasma spraying in this project. The thermal shock resistance ability of the three as-sprayed coatings will be measured by heating-water quenching method. The dynamic behavior of the crack propagation during thermal shock at high temperature will be investigated by extended finite element method.The evolution law of the cracks in the heat insulation layer of the three as-sprayed TBCs during thermal shock will be observed and characterized by Scanning Electron Microscope (SEM) and Acoustic Emission Method (AEM) in orer to further validate the simulaton results. The investigation results will exhibit dynamic images of the crack propogation in the heat insulation layers of the three as-sprayed TBCs at different thermal shock temperatures, and reveal the variation characteristic of t

英文关键词： Thermal barrier coatings；Thermal shock；Crack propagation；Modeling and simulation；Acoustic emission