Characterization of Exfoliated Graphite and Latex Composite as Temperature Sensors to Produce Thermal Images

Abstract

Temperature sensing is crucial in spacecraft to ensure all systems remain within operating temperatures. Sensing over an area would allow thermal management systems to effectively see the temperature profile in real time, which is not being done with thermocouple and RTD systems used today.

The resistance response as a function of temperature for exfoliated graphite and latex composite sensors was investigated. The effect of the substrate CTE and the EG loading level were observed and 30 wt% EG sensors were calibrated on a carbon fiber substrate. Above room temperature, the percent resistance change and temperature relationship is linear, while below room temperature the relationship is exponential. The resistance response from twelve sensor grids was converted into a temperature field to produce thermal images over a surface. These temperature profiles were compared to thermal simulation data, proving that the sensor grids successfully mapped the proper temperature patterns.