Multiscale thermomechanical modeling of frictional contact problems considering wear – Application to a pin-on-disc system

Abstract This paper presents a multi-scale strategy for thermomechanical simulation of frictional systems, as brakes, taking into account the scale of the contact interface phenomena which is much lower than the macro scale of the system. At macro scale, a finite element model is considered to model the system components. At micro scale, the thermal and mechanical contact problems are solved considering surface roughness and wear. At this scale, semi analytic methods, accelerated with the Fast Fourier Transform, and optimization techniques are used. As regards wear, Archard's law is used with a wear rate coefficient depending on temperature. From these models, contact parameters such as stiffness and heat partition coefficient are integrated into the macroscale model, and this for each surface element. Moreover, the solving scheme is transient allowing to update the surface topography under thermomechanical and wear effects. As an example, this multi-scale strategy is used to study the thermomechanical behavior of a pin-on-disc system. Moreover, implications of the interface on friction induced vibrations are also investigated. With this model, the influence of the interface behavior and wear on the system response, are clearly shown. Conversely this strategy gives results locally, close to the physical mechanisms involved in the contact. A comparison is performed with a classical model considering a perfect flat contact.