Abstract
By definition, Functionally graded materials (FGM) are new advanced composite materials which are used to produce components featuring engineered gradual transitions in microstructure and/or composition. FGMs permit tailoring of material composition so as to derive maximum benefits from their inhomogeneity. The aim of the study behind this contribution is to optimize the composition variation between the ceramic and the metal in order to minimize the maximum stress concentration around the hole in a plate made of FGMs in case of the plate is subjected to pressure, heating or both pressure and heating. The finite element method (FEM) has been used to optimize the material composition of functionally graded materials made from Al 1100 as the metal portion and SiC as the ceramic portion using the ANSYS package. The objective has been to minimize the stress concentration factor around a hole in a plate expressed by the ratio between the principal stress calculated by the ANSYS and the applied stress at different volume fractions of the metal and the ceramic. The investigations have shown that when applying pressure or heating to the plate the optimum for minimizing the stress concentration is to have a ceramic-rich plate and when the plate is subjected to both pressure and heating the optimality is to have a metal-rich plate.