A microwave resonance thin-film sensor for real-time wireless temperature monitoring in composites manufacturing

Composites are of growing importance to today's industries. Curing or consolidation under certain temperatures is a vital process to manufacture composite parts. Great attention has been paid to monitoring the temperature of composite parts being processed. Wireless monitoring methods are extensively explored for their unique advantages in realizing real-time monitoring of specific temperature distribution of the part. Here, a flexible microwave resonance sensor is first introduced to achieve real-time wireless temperature monitoring of composites. When applied to curing processes with different heating rates, it was found that the sensing relationship of the sensor was varied. Through in-depth analysis, the relationship between peak frequencies and temperature was established with consideration of different heating rates. In several curing processes with different heating rates, the mean error of the thin film sensor using a heating rate -related relationship was about 4.23 degrees C. which can be reduced by more than 43 % compared with the method using a static relationship.