Electrical resistance measurement for in situ monitoring of fatigue of carbon fabric composites

This study investigates whether fatigue damage can be monitored using the electrical resistance of the carbon fabric-reinforced thermoplastic. A four-probe method, using rivets for the current injection and conductive tape for the voltage measurement is presented. Quasi-static and hysteresis tests are presented to assess the method, with promising results. Then, fatigue tests at both 2 and 5 Hz are discussed. For the material under study, neither stiffness reduction nor permanent elongation occurred and therefore, fibre fracture is not the dominant mode of damage. As a result, the electrical resistance measurement was not capable of monitoring damage growth inside the specimen, since it is sensitive to fibre failure.