Abstract
In this study, conductive carbon nanofibers (CNFs) were dispersed into epoxy resin and then infused into glass fiber fabric to fabricate CNF/glass fiber-reinforced polymer (GFRP) laminates. The electrical resistance and strain of CNF/GFRP laminates were measured simultaneously during tensile loadings to investigate the in situ strain and damage monitoring capability of CNF/GFRP laminates. The damage evolution and conduction mechanisms of the laminates were also presented. The results indicated that the percolation threshold of CNFs content for CNF/GFRP laminates was 0.86 wt % based on a typical power law. The resistance response during monotonic tensile loading could be classified into three stages corresponding to different damage mechanisms, which demonstrated a good ability of in situ damage monitoring of the CNF/GFRP laminates. In addition, the capacity of in situ strain monitoring of the laminates during small strain stages was also confirmed according to the synchronous and reversible resistance responses to strain under constant cyclic tensile loading. Moreover, the analysis of the resistance responses during incremental amplitude cyclic tensile loading with the maximum strain of 1.5% suggested that in situ strain and damage monitoring of the CNF/GFRP laminates were feasible and stable.
Highlights
Fiber-reinforced polymer (FRP) composites are gaining increased importance as high performance structural materials in aerospace, automobile industries and civil infrastructure due to their high specific modulus and strength, good thermal stability and durability [1,2,3,4,5,6,7,8,9]
Different contents of carbon nanofibers (CNFs) were dispersed in epoxy resin and infused into four-ply unidirectional glass fiber fabric to fabricate CNF/glass fiber-reinforced polymer (GFRP) laminates
The electrical resistance was measured during monotonic, constant amplitude cyclic and incremental amplitude cyclic tensile loadings to investigate in situ damage and strain monitoring of CNF/GFRP laminates
Summary
Fiber-reinforced polymer (FRP) composites are gaining increased importance as high performance structural materials in aerospace, automobile industries and civil infrastructure due to their high specific modulus and strength, good thermal stability and durability [1,2,3,4,5,6,7,8,9]. FRP composites usually exhibit gradual degradation of mechanical properties during service, which is induced by the initiation and propagation of different levels of damages, such as matrix microcracks, interfacial debonding, delamination and fiber breakage [10,11]. Predicting these damage modes in advance will improve the reliability of FRP composites and prevent them from catastrophic structural failure. Glass fiber-reinforced polymer (GFRP) composites are the most-widely used FRP among composite materials globally due to their high performance to price ratio [12,13]. The strain and damage monitoring of GFRP composites during their long-term service is of significant interest.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
