Premium
Non‐quadratic defect energy: A comparison of gradient plasticity simulations to discrete dislocation dynamics results
Author(s) -
Bayerschen Eric,
Stricker Markus,
Weygand Daniel,
Böhlke Thomas
Publication year - 2016
Publication title -
pamm
Language(s) - English
Resource type - Journals
ISSN - 1617-7061
DOI - 10.1002/pamm.201610139
Subject(s) - misorientation , plasticity , materials science , exponent , quadratic equation , strain hardening exponent , grain boundary , slip (aerodynamics) , dislocation , hardening (computing) , mechanics , condensed matter physics , crystallography , geometry , composite material , thermodynamics , physics , mathematics , chemistry , microstructure , philosophy , layer (electronics) , linguistics
A small‐deformation strain gradient plasticity (GP) model for single‐crystals has been proposed in [1], including a grain boundary (GB) yield condition without hardening. It has been extended by a hardening term for the GBs after a comparison to discrete dislocation dynamics (DDD) results in [2]. Differences between the strain gradients of the GP results and the DDD results motivate the consideration of a non‐quadratic defect energy [3] in the GP model. It is shown that the gradients in the GP model can be improved using an exponent different from two. Remaining discrepancies in the strain profiles, compared to the DDD results, are attributed to the neglect of the individual gradients of plastic slip and due to the lack of a mechanism for the misorientation‐dependent elastic interactions of dislocations across GBs [4] in the GP model. (© 2016 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)