Non-intrusive health monitoring of infused composites with embedded carbon quantum piezo-resistive sensors

Fibre reinforced polymer composites (FRP) are developing faster than ever in fields such as aeronautics, automotive, naval or energies requiring materials with high toughness/weight ratio, to lower their environmental footprint. However, one brake to FRP development is that their damage can initiate without warning signs, due to unexpected overload, chocks, fatigue or defects. Structural health monitoring (SHM) aims to secure their use by anticipating their catastrophic fracture and make predictive maintenance. Existing solutions are using combinations of fibre Bragg gratings and ultrasonic sensors to follow strain evolution and cracks propagation in the composite. Here we present a new generation of nanocomposite quantum resistive sensors (QRS) that can be homogeneously introduced in FRP to sense their health without sacrificing their integrity. QRS as thin as 1.5 mu m, have been implemented on E-glass fibres (GF) before infusion of epoxy resin (EP). They allow to follow both strain and damages in both elastic and plastic domains up to failure with high sensitivity, i.e., gauge factors (GF) up to 6. (C) 2016 Elsevier Ltd. All rights reserved.