TY - JOUR
T1 - Energetic dislocation interactions and thermodynamical aspects of strain gradient crystal plasticity theories
AU - Ertürk, I.
AU - Dommelen, van, J.A.W.
AU - Geers, M.G.D.
PY - 2009
Y1 - 2009
N2 - This paper focuses on the unification of two frequently used and apparently different strain gradient crystal plasticity frameworks: (i) the physicallymotivated strain gradient crystal plasticity models proposed by Evers et al. (2004a,b) and Bayley et al. (2006, 2007) (here referred to as Evers-Bayley type models), where a physical back stress plays the most important role and which are further extended here to deal with truly large deformations, and (ii) the thermodynamically consistent strain gradient crystal plasticity model of Gurtin (2002-2008) (here referred to as the Gurtin type model), where the energetic part of a higher order micro-stress is derived from a non-standard free energy function. The energetic micro-stress vectors for the Gurtin typemodels are extracted from the definition of the back stresses of the improved Evers-Bayley type models. The possible defect energy forms that yield the derived physically-based micro-stresses are discussed. The duality of both type of formulations is shown further by a comparison of the micro-boundary conditions. As a result, this paper provides a direct physical interpretation of the different terms present in Gurtin’s model.
AB - This paper focuses on the unification of two frequently used and apparently different strain gradient crystal plasticity frameworks: (i) the physicallymotivated strain gradient crystal plasticity models proposed by Evers et al. (2004a,b) and Bayley et al. (2006, 2007) (here referred to as Evers-Bayley type models), where a physical back stress plays the most important role and which are further extended here to deal with truly large deformations, and (ii) the thermodynamically consistent strain gradient crystal plasticity model of Gurtin (2002-2008) (here referred to as the Gurtin type model), where the energetic part of a higher order micro-stress is derived from a non-standard free energy function. The energetic micro-stress vectors for the Gurtin typemodels are extracted from the definition of the back stresses of the improved Evers-Bayley type models. The possible defect energy forms that yield the derived physically-based micro-stresses are discussed. The duality of both type of formulations is shown further by a comparison of the micro-boundary conditions. As a result, this paper provides a direct physical interpretation of the different terms present in Gurtin’s model.
U2 - 10.1016/j.jmps.2009.08.003
DO - 10.1016/j.jmps.2009.08.003
M3 - Article
SN - 0022-5096
VL - 57
SP - 1801
EP - 1814
JO - Journal of the Mechanics and Physics of Solids
JF - Journal of the Mechanics and Physics of Solids
IS - 11
ER -