Monitoring of the curing process of composite structures by tunnelling junction sensors
Résumé
In this work, tunnelling junction sensors (TJS) are proposed for monitoring the curing of Carbon Fibre Reinforced Plastic (CFRP). Tunnelling junction sensors are very sensitive to temperature changes; therefore they are suitable for this application. TJS are manufactured by Low-Pressure Chemical Vapour Deposition (LPCVD) and electronically characterized to obtain their V(I) diagram. One sensor is embedded on a carbon\textendashepoxy plate for measuring temperature evolution during composite\textquoterights autoclave cycle. By means of a temperature\textendashvoltage\textendashtime curve, the evolution of sensor\textquoterights signal related to temperature changes can be tracked. The main goals are to verify the viability to apply this technology to composite\textquoterights curing process and to provide a first approach of the initial state of the composite plate by verifying the temperatures at each curing stage. Both purposes were achieved and help to better understand the composite polymerization process, which has a strong influence on the composite\textquoterights mechanical performance.