1600℃范围内热障涂层体系宏微观力学性能实时表征及破坏机理研究

如何发展新型实验测试技术和仪器设备，在不同服役温度下实时研究热障涂层体系宏微观力学性能和高温失效机理，是进一步完善涂层制备工艺、提高涂层构件服役寿命的重要途径，正成为国内外材料界和力学界的热点科学问题。本申请项目通过组装一套数字图像相关技术三维变形光学测试系统和高温加载设备，发展一种在1600度服役温度范围内实时表征热障涂层体系宏微观力学性能的新方法，原位观察涂层/基底体系的三维应变场动态演变、裂纹扩展过程，同步记录涂层失效的临界破坏条件；应用相关力学模型，建立涂层材料参数随服役温度变化的数据库；并进一步揭示在不同服役温度下热障涂层体系失效准则和宏微观破坏机理，为加快优化涂层制备工艺、有效评估热障涂层体系服役性能提供重要的实验支持，具有重要的科学意义和社会价值。

Novel experimental measurement techniques and apparatus are expected to be developed to in-situ study the high-temperature mechanical behaviors and failure mechanism of thermal barrier coating systems under different scales. It may be become important paths to improve the coating preparation properties and enhance the operation life of the coatings. The points have become hot questions in materials and mechanics fields. We will assemble a setup of digital image correlation three-dimensional strain test system and high-temperature load system, which may be used to real time study the mechanical characteristics and possible failure mechanisms of thermal barrier coating systems under macro or micro scales within 1600 degrees centigrade. Evolution of cracking nucleation, propagation and coating spallation would be in situ monitored by digital image correlation system. A lot of important experimental data and fracture phenomena can be recorded by computer. Other material properties of thermal barrier coating systems can be estimated by modified mechanics models and the above obtained critical data. These results are helpful for establishing many failure criteria, and revealing novel failure mechanisms, and predicting the service life of the coatings in practice.