Research On Flexible Temperature And Pressure Sensor Based On Thin Film Thermocouple And Cotton Fiber

Real-time monitoring of temperature and pressure plays a pivotal role in the fields of intelligent manufacturing,aerospace,metallurgy and steelmaking,medical and health,and automobile safety.With the development of flexible electronic technology,traditional temperature and pressure sensors with rigid substrates can't meet the special requirements such as wearable and complex curved surfaces,therefore flexible temperature and pressure sensors with high performances,low cost,easy integration,simple preparation and environmentally friendly are urgently needed now.This thesis conducts research on the flexible temperature and pressure sensor based on the thin film thermocouple and cotton fiber,main including:1.The temperature test platform was built,which can realize the temperature measurement of 15??200?.The flexible temperature sensor based on polyimide film was prepared by DC sputtering method.The thermo-electromotive force-temperature curve of the sample's temperature rise and fall process was tested,indicating that the sensor showed excellent performances of high sensitivity(S=38.2?V/?),good linearity(R²=0.9978),fast response(?=0.32s),good repeatability,high stability and low hysteresis.2.The cotton fiber was carbonized at high temperature and treated with TPU solution as a pressure-sensitive layer,which was packaged like a sandwich with the interdigital electrode to form the flexible pressure sensor.The reasons for the conductivity and flexibility of the pressure-sensitive layer were analyzed by SEM,Raman,and XPS.The piezoresistive performance test found that the sensor showed good process repeatability,high sensitivity of 1.553k Pa^-1,good linearity,rapid response/recover time(<80ms/<60ms),excellent stability and high durability(>8000 cycles).3.The application of the prepared sensor was studied.The array flexible temperature sensor was prepared,which can obtain the temperature distribution of the hot plate accurately.The flexible pressure sensor was applied to the quality measurement of small objects,human pulse and limb movement monitoring,which can get accurate response.The array flexible pressure sensor was also prepared,which laid the foundation for obtaining continuous pressure distribution.The flexible temperature and pressure sensor were combined to test the temperature and weight changes of the beaker with hot water.It can accurately sense the temperature of the beaker wall and the weight of the water,which has a broad application prospect.