Thermal buckling analysis of a functionally graded microshell based on higher-order shear deformation and modified couple stress theories

Abstract

In this study, thermal buckling responses of a functionally graded (FG) cylindrical microshell are investigated. Material properties of the FG microshell are considered to be graded through the thickness based on a simple power-law distribution. The governing equations and associated boundary conditions are derived based on classical higher-order shear deformation theory. Size dependence of the FG microshell is properly characterized based on the modified couple stress theory (MCST). Two types of differential quadrature method (DQM) – polynomial based differential quadrature (PDQ) and Fourier expansion based differential quadrature (FDQ) – are adopted to transform the differential equations into algebraic equations. The standard eigenvalue equation in the whole computational domain is subsequently established to obtain critical buckling temperature. The present numerical technique shows very fast convergence speed and is validated by comparison with available data in the open literature. Parametric studies are provided to demonstrate the influences of the temperature distribution profile, edge boundary conditions, length scale parameter, length-to-radius ratio, FG power-law index on the critical buckling temperature. In addition, the values of critical thermal buckling loads predicted by classical and MCST models are compared.