热障涂层中热生长氧化物的固体反应流理论

项目名称： 热障涂层中热生长氧化物的固体反应流理论

项目编号： No.11472203

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： 张伟旭

作者单位： 西安交通大学

项目金额： 95万元

中文摘要： 固体反应流指包含化学反应的固体塑性流动理论。不同的化学反应机理对应的反应流理论也有区别。目前关于锂电池与凝胶等化学反应变形方面已经有相应的固体反应流理论。然而金属氧化与塑性变形的固体反应流理论并未完全建立。金属氧化有以下特点导致其反应流理论的特殊性：（1）反应过程中氧化物相与金属相相共存，存在相边界；（2）反应在氧化物中发生；（3）随反应的进行，合金的氧化物可发生相变。热障涂层中TGO生长流动过程是典型的固体反应流过程。本研究拟建立热障涂层中TGO生长与变形的固体反应流理论。该理论满足Wagner氧化理论，包含化学-热-力耦合关系，并能够计及固体反应中的相变。首先通过实验分析TGO中的反应机理、形貌、及应力分布。利用Gibbs化学热力学原理建立固体反应流本构，预测TGO的反应流动，并用实验测试结果进行校核。该理论将不仅适用于热障涂层中TGO的反应流动，也适用于其他存在相分离的固体反应流动。

中文关键词： 热障涂层；化学反应；反应流；本构模型；多场耦合

英文摘要： Reactive flow in solids is the concurrent plastic flow with chemical reaction. It is different corresponding to different reaction mechanisms.There are already, some reactive flow theories now, such as on the lithium-ion batteries and on gels. However, there has not been perfect theory on the plastic flow with oxidation of metal. The following special features of metal oxidation induce the difference of reactive flow theory. (1) The phases of oxides coexist with phases of metals and there are sharp phase boundaries.(2) The oxidation occurs, in fact, in the oxide scale due to the inner diffusion of ions.(3) There may be phase transformation in the process of oxidation. The growth and plastic flow of TGO in thermal barrier coatings (TBCs) is a typical reative flow. This project is aimed to set up a reactive flow theory corresponding to the TGO in TBCs. Wagner's oxidation mechanism of solids are adopted. The chemo-thermo- mechanical coupled effect the phase transformation in oxidation process are considered in this theory. Firstly, we will investigat the oxidation mechanism, the morphology and the stress distribution in TGO through experiments. Then we will set up the reative flow theory by Gibbs's thermodynamical theory to predict the plastic deformation of TGO.The theoratical results will be testified by the experiments. This theory will not only be valid for the TGO growth in TBCs, but also valid for other solid reaction with phase transformation.

英文关键词： Thermal Barrier Coating;Chemical Reaction;Reactive Flow;Constitutive Model;Multi-Field Coupling