Thermal buckling and vibration analysis of rotating porous FG GNPs-reinforced Reddy microplates

Abstract

Thermal buckling and free vibration analysis of rotating functionally graded (FG) graphene nanoplatelets (GNPs) reinforced nanocomposite porous metal-matrix microplates subjected to a linear thermal gradient are presented in this paper. The third-order shear deformation theory (TSDT) of Reddy and the Lagrange's equation of the second kind are adopted to derive the governing equations of motion via the modified couple stress theory (MCST). Different patterns of porosity distribution and GNPs dispersion are considered. The effective material properties of the microplate are determined by employing the Halpin-Tsai micromechanical model and rule of mixture. Galerkin method is chosen as a numerical technique, in which the comparison functions for displacements are approximately described as the boundary functions multiplied by Chebyshev polynomials, to solve the governing equations for various boundary conditions. The accuracy and effectiveness of the present results are validated by comparing with the previous literature. The effects of GNPs dispersion pattern, geometry and weight fraction as well as porosity coefficient, porosity distribution, angular velocity and material length scale parameter on the critical buckling temperature rise and fundamental frequency are studied. It is contrary to expectations that either increasing the amount of GNPs or increasing the porosity coefficient improves the thermal buckling behavior. Results also show that the GNPs' performances are affected not only by their geometry, but also by the centrifugally stiffening and small-scale effects. Rotating motion weakens the enhancement of GNPs on the thermal buckling behavior. More clamped boundaries enhance the critical buckling temperature rise and fundamental frequency. The outcomes of this work can be used as the reference for future applications in various fields of industry and technology.