Volume fraction optimization for step-formed functionally graded plates considering stress and critical temperature

Step-formed Functionally Graded Materials (FGMs) flat panels are investigated for volume fraction optimization by considering stress and critical temperature. The structure is composed of numerous layers with homogeneous and different isotropic material properties from ceramic to metal. Material properties are assumed to be temperature dependent, and remain constant in each layer. Further, the properties are assumed to be varied in the thickness direction according to a simple power law distribution in terms of the ceramic and metal volume fractions for the layer. The effective material properties of the plate are obtained by applying linear rule of mixtures for the layers. The 3-D finite element model is adopted to analyze more accurately the variation of material properties and temperature field in the thickness direction. For the various FGM volume fraction distributions and geometric parameters, mechanical stress analysis and thermo-mechanical buckling analysis are performed to get the critical conditions. Based on the results, the volume fraction optimization of the flat panels is performed for stress reduction and improving thermo-mechanical buckling behavior and compared with previous results. (C) 2009 Elsevier Ltd. All rights reserved.