Modélisation du comportement thermomécanique des plaques FGM (Functionally Graded Materials)

Abstract

The aim of this thesis is to analyze the mechanical behavior of thick plates functionally graduated in a thermal environment. Therefore, this work investigates a thermomechanical bending analysis of functionally graded sandwich plates by proposing a new quasi-3D type. The mathematical model introduces only five variables as for the first order shear deformation theory (FSDT). Contrary to conventional high-order deformation theories (HSDT). The present model adopts a new field of displacement which includes indeterminate integral variables. The mechanical properties of the functionally graduated layers of the plate are assumed to change in the direction of thickness according to a power law distribution (P-FGM). The core layer is homogeneous and made of an isotropic ceramic material. The governing equations for the thermomechanical bending investigation are obtained through the principle of virtual work and solved via Navier-type method. Interesting results are then compared with others in the literature. Parametric studies are thus elaborated to see the influence of the characteristics geometric and mechanical in particular: thickness of the layer of the functionally graduated material (FGM), power law index, material index and ratio (Width, length) / thickness of the plate on the boom and the stresses of the thick plates.