Thermo mechanical properties of Carbon-Carbon composite (C/C) allow them to support high temperatures without hard degradation. It is probably the main reason for their utilisation in industrial applications such as plane brake manufacture where are submitted to hard tribological stress (pressure and shear) during the landing phase.

To understand their behaviour under such solicitations, the use of numerical tools appears as essential and thus for two principal reasons: the expensive cost of experimental tests as well as their limitations and their multi-scale feature.

Tools such as Finite element methods (FEM) (3) allow to separate the different scales and phenomena, and consequently to bring out their different role and to determine their impact on the dynamical behaviour of a contact. But using heterogeneous models to study the dynamical behaviour of such composites could lead to long time simulations. If numerical approaches such as homogenization techniques could be really efficient, the main difficulty is to use such techniques under dynamical contact conditions.

The present paper present the results based on an approach coupling an explicit integration of dynamics and an implicit global treatment of contacts (1). The local contact problem is solved using Lagrange multipliers and a Prakash-Clifton (5) law to manage the local friction. Comparison have been made between different heterogeneous models, called morphologies and the corresponding homogeneous model. The contact contrast is investigated (deformable/rigid (2) or deformable/deformable/contact (4)) and in each cases, instabilities regimes and morphologies are connected. Results are compared in terms of global friction amplitude, dissipated energy and instability regimes.

Mbodj Coumba, Berthier Yves - Université de Lyon Renouf Mathieu* - Université Montpellier 2