Computational and theoretical aspects of a grain-boundary model that accounts for grain misorientation and grain-boundary orientation

A detailed theoretical and numerical investigation of the infinitesimal single-crystal gradient-plasticity and grain-boundary theory of Gurtin (2008) is performed. The governing equations and flow laws are recast in variational form. The associated incremental problem is formulated in minimisation form and provides the basis for the subsequent finite element formulation. Various choices of the kinematic measure used to characterise the ability of the grain boundary to impede the flow of dislocations are compared. An alternative measure is also suggested. A series of three-dimensional numerical examples serve to elucidate the theory. (C) 2015 Elsevier B.V. All rights reserved.