In dry high speed machining of aluminium alloy AA2024-T351, the thermomechanical process of chip formation, the tool wear and the surface integrity depend strongly on the tribological conditions along the tool rake face. In the present work, we propose a hybrid Analytical-FE model taking into account the thermomechanical coupling between the chip formation process and the sticking-sliding conditions at the tool-chip interface. The transient nonlinear thermal problem in the tool-chip-workpiece system is solved by using a Petrov-Galerkin finite element model. The model has been compared to the experimental data for a wide range of cutting speeds. This comparison shows a good agreement in both trends and values for cutting forces and tool-chip contact length. It has been also observed that a transition from a sliding contact to a sticking-sliding contact occurs when the local friction coefficient and the thermal softening are large enough.