AbstractHighly dynamic problems can be well described using multi‐body systems. Nevertheless this method is limited to systems whithout large elasto‐plastic deformations that can e.g. be found during an extrusion process. To model such a system, multi‐body systems can be adequately combined with special particle approaches like the mesoscopic particle method [1], [2]. These mesoscopic particles have internal variables describing hidden degrees of freedom. Interaction forces between particles similar to those on the atomic scale have to be taken into account to describe phase transitions. So materials' properties concerning temperature and pressure can successfully be reproduced. This paper therefore deals with the description of an extrusion process in the multi‐body frame using mesoscopic particles. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)