A slice model for thermoelastic analysis of porous functionally graded material sandwich beams with temperature-dependent material properties

Abstract

Porosity usually occurs in functionally graded materials (FGMs) during the fabrication process. Its effects on the thermomechanical behaviors of FGM structures are worth studying. In this work, heat transfer and thermoelastic behaviors of porous FGM sandwich beams with temperature-dependent material properties are examined. The effective material properties are approximately estimated by the modified Voigt mixture rule. Because of the continuously varied material properties across the thickness direction, it is impractical to seek exact solutions for the beam. By proposing a slice model in which the face and core layers are divided into numerous thin slices, the material properties of each slice can be treated as uniform. Based on the model, the through-thickness temperature distribution is first obtained by using an iteration algorithm. Then the two-dimensional (2-D) thermoelasticity equations are analytically solved by using the state space method and Fourier series expansion method. The correctness of the proposed model is checked through comparison with results reported in previous works. The effects of some key factors such as the temperature dependence of material properties, volume fraction, and porosity on the thermomechanical behaviors of the beam are comprehensively studied. It is shown that with the increase of porosity, the thermal resistance capacity of the beam is enhanced yet the bending stiffness is weakened.