Numerical simulation of industrial plastic deformation processes needs of a precise characterization of the mechanical material properties included in the particular elastoplastic model. The plasticity model of bulk metallic materials is well known and the tests used for characterization are simple and well typified. The situation is quite different when the compaction of metal and ceramic powder has to be simulated; in this case, both, plasticity models and the corresponding mechanical tests are under discussion and research. Irrespective of the plastic model being employed more parameters and more complex than in the case of bulk materials must be determined. In this work the experience gained in this field by the joint effort of the research groups participating in the recently finished European Network Dienet is presented