Thermoelastic instability of functionally graded materials in frictionless contact

Abstract

This paper investigates the static thermoelastic instability between a functionally graded material (FGM) half-plane and a homogeneous half-plane under the plane strain state using the perturbation method. Two frictionless half-planes are pressed together by a uniform pressure and transmit a uniform heat flux at their interface where a pressure-dependent thermal contact resistance is taken into account. The material properties of the FGMs are assumed to be of an exponential form. The characteristic equation is derived to determine the thermoelastic instability behavior of two half-planes. The instabilities are categorized into three types based on the ratio of the material properties. The effects of the gradient index, thermal contact resistance and material combination on the critical heat flux are discussed by the parametric studies. It is indicated that the use of FGMs can improve the thermoelastic instability behavior of systems.