Thermoelastic frictional contact of functionally graded materials with arbitrarily varying properties

This paper investigates the thermoelastic frictional contact of functionally graded materials (FGMs) with arbitrarily varying thermoelastic properties. The homogeneous multi-layered model is used to approximate the arbitrarily varying material properties of the FGM coating which is divided into several sub-layers whose material properties is assumed to be constant. It is assumed that a rigid insulated punch is sliding over the surface of an FGM coated half-plane with a constant velocity, which generates frictional heating at the contact interface with its value proportional to the contact pressure, frictional coefficient and sliding velocity. The transfer matrix method and the Fourier integral transform technique are employed to convert the problem into Cauchy singular integral equations which are then numerically solved to obtain the contact stress, in-plane stress and surface temperature. The effects of the gradient index, Peclet number and friction coefficient on the thermoelastic contact characteristics are discussed in detail. Different gradient types of FGMs are considered in numerical examples to compare and identify effective gradient type in suppressing the maximum tensile stress and lowering the maximum surface temperature. Numerical results indicate that thermoelastic contact damage behavior can be changed by adjusting the Peclet number, friction coefficient and their gradient indices or gradient type