Modeling Dislocation Sources and Plastic Flow through Grain Boundaries in Mesoscopic Field Dislocation Mechanics
نویسندگان
چکیده
................................................................................................................ ii ACKNOWLEDGEMENTS ...................................................................................... iv LIST OF FIGURES ................................................................................................. viii LIST OF TABLES .................................................................................................... xii LIST OF NOTATIONS........................................................................................... xiii OVERVIEW.................................................................................................................1 1.1 MOTIVATION.............................................................................................................1 1.2 LITERATURE REVIEW: THEORETICAL MODELS........................................................3 1.3 CURRENT WORK (OUTLINE).....................................................................................5 1.4 NOTATION AND TERMINOLOGY................................................................................7 SMALL DEFORMATION FIELD DISLOCATION MECHANICS THEORY...9 2.1 THEORY ....................................................................................................................9 2.2 CONSTITUTIVE RESPONSE BASED ON THERMODYNAMICS.....................................14 2.3 CONSTITUTIVE SPECIFICATION...............................................................................21 2.4 NUMERICAL FORMULATION ...................................................................................25 2.5 ALGORITHM............................................................................................................28 2.6 PARALLELIZATION OF THE CODE ...........................................................................28 MODELING DISLOCATION SOURCES AND SIZE EFFECTS AT INITIAL YIELD IN CONTINUUM PLASTICITY ...............................................................32 3.1 RESULTS AND DISCUSSION.....................................................................................33 3.2 CONCLUSIONS.........................................................................................................44 GRAIN BOUNDARIES IN CONTINUUM PLASTICITY MODEL...................55 4.1 SOLVING FOR z .....................................................................................................56 4.2 JUMP CONDITION FOR EXCESS DISLOCATION DENSITY (ED) ................................57
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