Buckling and free vibration analysis of randomly distributed CNT reinforced composite beam under thermomechanical loading

Abstract

In this study, the buckling and free vibration characteristics of three-phase randomly distributed carbon nanotube (CNT) reinforced fiber composite (RD-CNTRFC) beams subjected to in-plane compressive loadings and thermal environment are discussed in-depth through a semi-analytical approach. Displacement-based governing equations of motion are derived using Lagrange equation considering higher-order shear deformation theory (HSDT). The effective material properties of RD-CNTRFC are determined in two stages; firstly, effective properties of hybrid matrix (CNTs + Polymer) are evaluated using the Eshelbhy-Mori-Tanaka approach. Finally, overall effective properties of CNTRFC are estimated by implementing different homogenization techniques. The influences of temperature-dependent material properties and CNT-agglomeration are included in the derived formulation. The buckling loads and natural frequencies of RD-CNTRFC beams are computed using a typical eigenvalue solution. The influence of various boundary conditions, CNT mass fraction, CNT-agglomeration, length-to-thickness ratio, and various ply sequences are also addressed.