As expected, it is observed that the necessary loads for the simulated direct extrusion processes are greater than the ones  required for indirect extrusion under the same friction conditions. This is due to the contact of the billet with the container before being extruded through the extrusion die. In direct extrusion, the material is displaced by the punch along the container and it is affected by the  friction with the container walls.  In  indirect extrusion this does not occur, as it can be observed in Figure 2;  therefore, in comparison with direct extrusion,  friction at the container walls, Fc, is negligible and the necessary force to run the process is lower. By comparing the load results of direct and indirect processes, it can also be identified the contribution of friction at the die,  Fdie, to the friction load. The maximum friction load contribution due to the die-billet contact in cup extrusion is much higher than in the case of solid extrusion. On the contrary, the maximum friction load contribution due to the container wall is much higher in the case of solid extrusion than in cup extrusion. Required loads for the same extrusion ratio are higher in cup extrusion processes than in solid extrusion ones. Thus, the analysis performed allows  the estimation of the maximum effect of friction  in the four extrusion processes, and to clearly identify the contributions of friction at the container walls and the extrusion die. In future works this analysis will be extended to more complex geometries of the extrudates and to the extrusion of advanced materials such as high strength steels whose formability is poor compared to other metallic alloys. This will lead to broaden the application field of extrusion processes  and  to investigate their limitations in order to improve their performance in future industrial scenarios. 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