Thermomechanical buckling and wrinkling characteristics of softcore sandwich panels with CNT reinforced composite face sheets

Abstract

This article explores the local and global stability of CNT reinforced composite (CNTRC) sandwich shell panels consist of softcore material. The shell panel's face sheets are reinforced with functionally graded nanotube particles. The effective properties of CNTRC face sheets are determined considering the extended rule of mixture technique, and a multi-layer approach is used to examine the local and global stability phenomena. The material properties of the face sheets are assumed to be temperature-dependent. The formulation account for the core compressibility effect by considering higher-order polynomial terms for transverse core displacement. The governing equations for each layer of the sandwich panel are derived by minimizing the total potential energy of the system. The Galerkin's technique is adopted to obtain a set of non-linear algebraic equations from the derived partial differential equations. Global buckling and wrinkling loads of sandwich shell panels under thermomechanical loadings are obtained by solving standard eigenvalue problem. The nonlinear responses for sandwich shell panels subjected to mechanical and thermal stresses are traced through the arc-length approach and iterative approach, respectively. The obtained responses elucidate the influence of CNT gradation, volume fractions and core thickness on the local and global stability behaviour of CNTRC sandwich shell panels.