ABSTRACT
Concerning rotations at contact, the crude introduction of rotations for any particle, whatever the nature of its contacts with other particles, does not seem realistic in the case of powder compaction for which contact plasticity is the main deformation mechanism. Thus, we prefer to make the reasonable assumption that rotation of a particle is only possible when all its contacts behave elastically. This assumption can be alternatively understood by stating that above a certain size, contacts are large enough to oppose any rotation.
