Thermoelastic wheel–rail contact problem with elastic graded materials

Graded materials are generally two-phase composites with continuously varying volume fraction. Numerous experiments indicate that used as the coatings attached to the conventional steel body and interfacial zones they can reduce the magnitude of mechanically and/or thermally induced stresses. In this paper the wheel–rail contact problem including friction, frictional heat generation as well as heat transfer across the contact surface and wear is considered. The rail is assumed to be covered with a coating. The thermal and mechanical properties of the coating material depend on its depth and are governed by the power law. Moreover it is assumed that the heat flow is governed by conductive equation in a coating layer and inside the rail. In the paper quasistatic approach to solve numerically this rolling contact problem is employed. This approach is based on the assumption that for the observer moving with the rolling wheel the displacement or temperature of the supporting foundation are independent on time. Finite element method is used as a discretization method. Numerical results are provided and discussed.

Research highlights▶ Rail surface covered with functionally graded material. ▶ Wheel–rail contact with friction and heat flow. ▶ Quasistatic transformation of the original rolling contact problem. ▶ Numerical method based on fixed point algorithm. ▶ Reduction of normal stress or maximal temperature in contact zone.