  The two key phenomena occurring in the process of ceramic powder compaction
are the progressive gain in cohesion and the increase of elastic stiffness,
both related to the development of plastic deformation. The latter effect is an
example of `elastoplastic coupling', in which the plastic flow affects the
elastic properties of the material, and has been so far considered only within
the framework of small strain assumption (mainly to describe elastic
degradation in rock-like materials), so that it remains completely unexplored
for large strain. Therefore, a new finite strain generalization of
elastoplastic coupling theory is given to describe the mechanical behaviour of
materials evolving from a granular to a dense state. The correct account of
elastoplastic coupling and of the specific characteristics of materials
evolving from a loose to a dense state (for instance, nonlinear --or linear--
dependence of the elastic part of the deformation on the forming pressure in
the granular --or dense-- state) makes the use of existing large strain
formulations awkward, if even possible. Therfore, first, we have resorted to a
very general setting allowing general transformations between work-conjugate
stress and strain measures; second, we have introduced the multiplicative
decomposition of the deformation gradient and, third, employing isotropy and
hyperelasticity of elastic response, we have obtained a relation between the
Biot stress and its `total' and `plastic' work-conjugate strain measure. This
is a key result, since it allows an immediate achievement of the rate
elastoplastic constitutive equations. Knowing the general form of these
equations, all the specific laws governing the behaviour of ceramic powders are
finally introduced as generalizations of the small strain counterparts given in
Part I of this paper.
