Development of Integrated Process and Structural Health Monitoring System Based on Piezosensors for CFRP Reinforcements Made by Resin Transfer Molding

摘要

Within this paper the authors present the latest simulation and testing results of a novel integrated process and structural health monitoring concept based on piezo sensors. The basic idea is to place a number of piezo sensors on predefined positions over the RTM mold. In a first step the piezo sensors are operated as pressure sensors to monitor the flow front propagation in the mold. Once the whole fabric was impregnated by the resin and curing starts the impedance of the piezosensors is measured over the time. The change in the impedance spectra is used to determine the degree of cure. Finally, when the curing process is finished, all piezosensors are co-cured on the surface of the part and remain on the part to be used for structural health monitoring either in passive mode as acoustic emission sensors or in active mode using guided ultrasonic waves. Individual tests of the different parts of the integrated process and health monitoring system demonstrated the operability of the proposed concept. Finally a simplified component with the integrated process and health monitoring system was manufactured to validate the overall system performance.