Characterizing delamination toughness of laminated composites containing carbon nanotubes: Experimental study and stochastic multi-scale modeling

The influence of adding carbon nanotubes (CNTs) to matrix on the delamination resistance of laminated composites is evaluated experimentally and theoretically. A proper multi-scale modeling technique is developed for estimating the interlaminar fracture toughness of laminated composites containing CNTs. Therefore, all involved scales and corresponding parameters are taken into account. Non-bonded interaction is considered between CNT and polymer using adapted cohesive laws resembling CNT-polymer adhesion. The developed modeling is implemented stochastically to take into account the manufacturing-induced inconsistencies. CNT lengths, agglomeration, waviness patterns and orientations are all treated as random variables and thus a full stochastic multi-scale modeling procedure is conducted. Laminated composites with uni-directional glass fibers and epoxy resin reinforced with different portions of CNTs are fabricated for experimental analysis. The specimens are subjected to Mode-I loading and the delamination toughness of the specimens is measured. Considerable improvements are observed due to incorporating CNT as a novel technique to increase the delamination resistance of laminated composites. The outputs of the modeling procedure are in a very good agreement with conducted experimental study.

Automated summary

The study evaluated the influence of adding carbon nanotubes (CNTs) to laminated composites on delamination resistance through experimental and theoretical assessments. It was found that incorporating CNT as a novel technique can considerably improve the delamination toughness of laminated composites. The outputs of the modeling procedure showed good agreement with the conducted experimental study.