Modelling of Experimental Observations of Electrical Response of CNT Composites

Abstract

A physics based analytical models on prediction of electro-mechanical behavior of carbon nanotubes (CNTs) embedded epoxy composite are developed to investigate the change in resistance under quasi-static tensile and compression loading conditions. Two different types of contacts namely in-line and lateral contacts between CNTs were considered in predicting electrical tunneling of current. It was identified from experiments that the extent of these contacts vary during deformation and lateral contacts predominates after composite reaches maximum stress during deformation, resulting decrease in resistance. The non-linear constitutive response of the composite obtained from experimental results is incorporated into model to accommodate decrease/increase in distance between above contacts. Under tensile loading conditions, the model made decent predictions against experimental results for composites of three different weight fractions (0.1, 0.3 and 0.5 %) of CNTs. Later, this model is extended to predict electro-mechanical response for intermediate weight fractions. Our efforts are currently focused on developing model to predict electrical response under compression loading and the results of this model along with under tensile loading will be presented at the conference.