Reversible phenomena and failure localization in self-monitoring GNP/epoxy nanocomposites

The reversibility and failure detection and localization capabilities of sensors based on graphene nanoplatelets (GNPs) were tested. Results have shown that the strain sensing capability is reversible presenting no hysteresis and has been demonstrated to endure up to 50 cycles. It was elucidated that if a stationary load is applied, normalized electrical resistance increases and remains mainly constant while load is maintained. Once this load has been completely removed, the structure recovers the initial electrical resistance what reinforced the reversibility of the sensor. Additionally, developed GNP/epoxy sensors were demonstrated to detect and locate damage in the sample due to a breakage of the electrical network when failure occurs that could be differentiated from changes due to strain as they caused an abrupt increase.