Computational Modeling and Experimental Characterization of Macroscale Piezoresistivity in Aligned Carbon Nanotube and Fuzzy Fiber Nanocomposites

Abstract

In this study, a multiscale computational micromechanics based approach is developed to study the effect of applied strains on the effective macroscale piezoresistivity of carbon nanotube (CNT)-polymer and fuzzy fiber-polymer nanocomposites. The computational models developed in this study allow for electron hopping and inherent CNT piezoresistivity at the nanoscale in addition to interfacial damage at the CNT-polymer interface. The CNT-polymer nanocomposite is studied at the nanoscale allowing for interfacial damage at the CNT-polymer interface using electromechanical cohesive zones. For fuzzy fiberpolymer nanocomposites, a 3-scale computational model is developed allowing for concurrent coupling of the microscale and nanoscale. The electromechanical boundary value problem is solved using finite elements at each of the scales and the effective electrostatic properties are obtained by using electrostatic energy equivalence. The effective electrostatic properties are used to evaluate the relative change in effective resistivity and the macroscale effective gauge factors for the nanocomposites. In addition, the piezoresistive response of aligned CNT-polymer and fuzzy fiber-polymer nanocomposites is investigated experimentally. The results obtained from the computational models are compared to the experimentally observed change in resistance with applied strains and associated gauge factors.

Interface engineering of carbon fiber composites using CNT: A review

“…45° alignment of piezoelectric fiber with ACLD patches causes maximum performance of the patches. Chaurasia et al 171 developed a multiscale computational micromechanics‐based approach to study the effect of applied strains on the effective macroscale piezoresistivity of CNT‐polymer and fuzzy fiber‐polymer nanocomposites. They used FE modeling and electromechanical cohesive zones to model the CNT‐polymer interface.…”

Enhanced imaging of piezoresistive nanocomposites through the incorporation of nonlocal conductivity changes in electrical impedance tomography

“…Although such models are accurate on the micro-scale, they can be computationally burdensome to implement on the macro-scale. Computational micro-mechanics models use finite element methods to model representative volume elements (RVEs) consisting of nanofillers and the surrounding matrix material (Chaurasia et al, 2014a, 2014b; Ren et al, 2015, 2016). This approach is useful for understanding mechanical effects such as interfacial separation and damage evolution in nanocomposites.…”