考虑微观结构特征的热障涂层力-热-化学耦合失效机理研究

项目名称： 考虑微观结构特征的热障涂层力-热-化学耦合失效机理研究

项目编号： No.11472206

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 李跃明

作者单位： 西安交通大学

项目金额： 88万元

中文摘要： 热障涂层系统（TBCs）是燃气轮机高温叶片（1400度以上）的六大核心技术之一，其失效破坏直接威胁机组安全。TBCs 失效是尺度、物理等多因素作用的结果，对其机理的揭示面临复杂微观结构真实表征、多场作用失效理论及数值方法等挑战。 本项目拟构建TBCs 微观结构的精确表征方法，建立可考虑其微结构特征的扩散-氧化反应方程，以及可反映TBCs材料拉压不等的热-弹粘塑性本构模型；进而开展基于微结构模型的力-热-化学多场数值分析，研究微观结构、氧化扩散、高温软化、强度特性、蠕变粘性等因素对TBCs 失效机理的影响。 本项目通过计算材料学、化学、热学和力学等学科交叉，开展考虑微结构的力-热-化学三场作用研究，揭示TBCs多因素失效机理，为燃气轮机高温叶片TBCs设计与失效分析提供基础和方法。

中文关键词： 热障涂层；微观结构；力-热-化学耦合；失效机理

英文摘要： Thermal barrier coating system (TBCs) is one of the six core technologies for the high temperature gas turbine blades (above 1400?C). The failure of TBCs directly threatens the safety of gas turbine unit. TBCs failure is the result of many factors action,involving the aspects of scale, physical field and others. To reveal the failure mechanisms is facing the challenges how to characterize the complex microstructure accurately and to establish a multi-field effect failure theory and develop its numerical method. In this project, we will establish a accuracy finite element reconstruction method to characterize the microstructure of TBCs. Then a diffusion-oxidation model, condering the microstructural features of TBCs, will be proposed. Finally, by taking the TBcs material properties of tension-compression inequality into account, a thermal elastic-viscoplasticity constitutive model will be established. Eventually, the chemo-thermo-mechanical multi-field numerical analyses will be implemented to reseach the effects of microstructures, diffusion-oxidation, high-temperature softening, strength properties and creep viscosity on the failure of TBCs. Through the multi-disciplinary intersection of computational materials science, chemistry, thermodynamics and mechanics, the analyses of the chemo-thermo-mechanical coupling effects will be performed to study the multi-factor failure mechanisms of TBCs. The research will contribute to the design and failure analyses of TBCs for hot-end components of high-temperature gas turbine.

英文关键词： thermal barrier coating;microstructure;chemo-thermo-mechanical coupling;failure mechanism