Simulation, fabrication, and characteristics of high-temperature, quick-response tungsten-rhenium thin-film thermocouples probe sensor

In this study, a tungsten-rhenium thin-film thermocouples (TFTCs) is fabricated via magnetron sputtering on silicon carbide ceramics. Cuboid TFTCs probe is sealed with stainless steel shell to make the TFTCs probe sensor. This sensor has an average Seebeck coefficient of 27.2 μV °C-1 at 1167 °C (temperature difference). The thermal volatilization characteristics, electromotive force behavior, and response time of this tungsten-rhenium TFTC sensor are investigated. The real engine experimental results show that the TFTCs probe sensor can work normally under the high temperature and high-speed air flow environment of 4 Mach and 900 °C. In addition, the correlation between the response speed, substrate thickness, and film thickness is discussed based on simulations of the response to carbon dioxide laser pulses. As indicated by the dynamic experiment results, the laser response time is from 0.49 to 1.51 ms, which is much shorter than that of traditional armored C-type thermocouples (for tungsten-rhenium thermocouples, the response time is around 1 s). Tungsten-rhenium TFTCs probe sensor is a suitable alternative to conventional thermocouples to meet the requirements of measuring high temperatures with a quick response.