Optimization of the Temperature Detection System for the Key Components of the Turbine Based on Thin-Film Thermocouples

In response to the urgent need for temperature measurement in high - temperature and harsh environments,this study innovated a NiCr/NiSi thin film thermocouple based on magnetron sputtering process, which adopts non-planar structure design, breaking through the limitation of coplanar cold and hot ends of traditional flat film thermocouples. By optimizing sputtering parameters on the Al<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> ceramic substrate (power 200W, argon pressure 0.8Pa), a uniform deposition of 1μm thick electrodes was achieved, and a NiCrAlY transition layer was introduced to enhance the substrate bonding force. Static calibration shows that the average Seebeck coefficient of the thermocouple in the range of 10–340 °C is 40μV/°C, and the response time is less than 10ms, which is 30% higher than that of the standard K-type thermocouple. The unique microstructure design enables embedded temperature measurement in high temperature gas flow field, providing a new solution for transient temperature monitoring of key turbine components.