Stress Distributions in Nanocomposite Sandwich Cylinders Reinforced by Aggregated Carbon Nanotube

In order to improve the static response of thick hollow cylinders, a sandwich cylinder with two carbon nanotube (CNT)-reinforced nanocomposite face sheets are proposed in this article. Moreover, due to the use of optimum amount of high cost CNTs, the CNT distribution is suggested to be functionally graded (FG) along the thickness of cylinder. The stress and deflection profiles of the proposed sandwich cylinders subjected to internal and external pressures have been investigated using a finite element method (FEM) based on an axisymmetric model. The significant effect of formation of CNT agglomerations in the surrounded matrix is considered and the material properties of the resulted nanocomposite are estimated by Eshelby-Mori-Tanaka approach. Using the developed axisymmetric FEM model, the effects of CNT aggregation state, volume fraction, and distribution as well as geometrical dimension and loading condition on the stress and deflection distributions of the nanocomposite sandwich cylinders have been characterized. The extensive simulations have revealed that instead of adding higher volume fraction of CNT, the selection of suitable distribution for CNTs can lead to a nanocomposite sandwich cylinder with less deflection. (C) 2018 Society of Plastics Engineers