研究了一种直接沉积在镍基高温合金上的薄膜热电偶传感器。针对航空发动机高温恶劣环境, 设计了传感器的膜层结构, 采用磁控溅射技术沉积 NiCrAlY薄膜过渡层, 以电子束蒸发和射频磁控溅射技术相结合的方法沉积 Al2O3薄膜绝缘层和保护层, 采用直流磁控溅射技术制备 Pt10Rh/Pt薄膜敏感层。测试结果表明, 薄膜热电偶传感器最高工作温度达 1100℃, 塞贝克系数 8.26μV/℃, 最大温度误差小于 1%, 使用寿命大于 20h。该薄膜热电偶能够承受恶劣的航空发动机试验环境, 显著地提高局部温度测量的精度, 对涡轮叶栅的寿命预期和冷却结构设计提供了参考依据。

A thin film thermocouple sensor directly deposited on Ni-based superallo is studied in this paper. According to the high temperature and harsh environment of aero-engine, the layer structure of the sensor is designed. Using the magnetron sputtering technology to deposite the membrane transition layer of NiCrAlY, the thin film insulating layer and protective layer are fabricated by the method of E-beam evaporation and RF-magnetron sputtering techniques. The Pt10Rh/ Pt sensitive layers of thin-film are prepared by DC magnetron sputtering technology. Test results show that the maximum operating temperature is 1 100 ℃. The seebeck coefficient is 8.26 μV/℃. The maximum temperature error is 0.93%. The service life is over 20 h. The results show that the thin-film thermocouple can withstand the harsh test environment of aero-engine, and the accuracy of the measurement’s local temperature is improved. The important basis for the life expectancy of the turbine cascade and the design of cooling structure is provided.