石墨烯/Nd3+/Eu3+共掺杂温敏热障涂层的制备及光响应温度行为研究

针对热障涂层服役过程中内部温度无法实时反馈和控制，容易造成涂层氧化加速而过早失效的关键科学问题，本项目提出采用液料等离子喷涂技术制备石墨烯/Nd3+/Eu3+稀土离子共掺杂的温敏热障涂层，利用稀土元素发光性能与温度的映射关系，可实时监控涂层内部温度的变化趋势。首先通过石墨烯对Nd3+/Eu3+进行改性及成分调控，实现增强其发光强度的目的，其次通过各层掺杂不同含量石墨烯/Nd3+/Eu3+设计多层梯度结构，实现涂层厚度全范围内的发光强度随温度变化高灵敏响应性，最终通过研究发光强度与温度的映射关系、发光强度衰减特性与高温服役时间的关联性，实现有效评估热障涂层服役健康状况和准确预测其剩余寿命的目的，为温敏热障涂层基于光响应温度特性预警涂层失效奠定理论基础。

The internal temperature of thermal barrier coating is unable to get feedback in real-time and to control, which easily accelerates oxidation and leads to premature failure. In response to these key issues, graphene co-doped Nd3+ and Eu3+ rare earth ions (graphene/Nd3+/Eu3+) thermal barrier coating, which is temperature sensitive, will be prepared by liquid plasma spraying in this project. The internal temperature variations of coating can be monitored in real time by using the mapping relationship between the luminescent property and the temperature. First, the composition ratio between graphene and Nd3+/Eu3+ will be adjusted and optimized to enhance its luminescence. Then, to achieve the luminescent intensity in the full range of coating thickness with high sensitive response to varying temperature, a multilayered and graded structure with different graphene/Nd3+/Eu3+ ratio will be designed. Finally, the evaluation of service health status and the prediction of remaining life of the thermal barrier coating will be realized by establishing the mapping relationship between luminescent intensity and temperature, as well as the correlation between luminous intensity attenuation characteristic and service time in high temperature. This project will lay important theoretical foundations for predicting coating failure in view of light response temperature characteristics.