Buckling analysis of porous power-law and sigmoid functionally graded sandwich plates

In this study, an advanced shear deformation plate theory is proposed to analyze the buckling behaviour of functionally graded sandwich plates. A novel definition of porosity distribution which accounts for both material composition and sandwich plate architecture, is included. The material properties of the functionally graded material layers are assumed to vary continuously through the plate thickness, described by either a power-law or sigmoid function based on the volume fractions of materials. The core is a homogeneous ceramic layer, while the outer layers on both sides are considered functionally graded across thickness. The virtual displacement principle is used to formulate the governing equations. The Navier method is utilized to derive a closed-form solution for a simply supported rectangular plate. Numerical results are provided to demonstrate the influence of material distribution, sandwich plate geometry, and porosity on the buckling loads of FG sandwich plates. The proposed theory is compared with results from previous studies to validate the accuracy and reliability. The proposed theory is accurate and simple in solving the buckling behavior of porous power-law and sigmoid functionally graded sandwich plates FGM plates.