Thermo-mechanical buckling response of functionally graded sandwich dome structures

Abstract

This study investigates the static thermo-mechanical buckling analysis of various dome structures made of functionally graded materials (FGM). Spherical, cylindrical, elliptical paraboloid and hyperbolic paraboloid domes are considered. A series of equivalent three-layer sandwich plate configurations are evaluated using a high-order shear deformation theory (HSDT). The structures are designed to have a FGM and ceramic material with face layers of pure metal, pure ceramic, or a combination thereof, and up to 80% foam ratio in the core layer. The research focused on the thermo-mechanical behavior of sandwich dome structures with different face layers (pure metal face layers (MFM), mixed metal-ceramic face layers (NFN), and pure ceramic face layers (CFC)). In the study, the properties of the face layers and the FGM core layer, such as the foam ratio and dispersion type of the core layer, were extensively investigated. In addition, the effect of the geometric shape of the dome structure (spherical, cylindrical, elliptical paraboloid and hyperbolic paraboloid) on the radius of curvature is investigated. The equations of motion are derived using Hamilton’s principle and the Navier method is applied for their solution. It is concluded that the thermo-mechanical buckling behavior of the dome structure is affected by factors such as the type of sandwich structure (CFC, NFN and MFM), the presence of functional porous material in the core and geometrical properties. According to the data obtained, it was found that the thermal resistance of the dome structure increases when the foam ratio reaches 50%, but when it exceeds this ratio, the thermal resistance starts to decrease.