Skip to Main content Skip to Navigation
Theses

Ductility criterion based on ellipticity loss of the elastic-plastic tangent modulus deduced from a self consistent model

Abstract : THE AIM OF THIS PHD THESIS IS TO MODEL A DUCITLITY LOSS CRITERION. TO DO THAT, THIS WORK HAS BEEN DONE IN THREE STEPS. IN A FIRST TIME, THE BEHAVIOR AT THE LOCAL SCALE (WHICH IS THE ONE OF A GRAIN OR A SINGLE CRYSTAL) HAS BEEN MODELED BY A MICROMECHANICAL LAW WRITTEN IN THE LARGE STRAIN FRAMEWORK. HARDENING IS, AS FOR IT, TAKEN INTO ACOUNT BY A MATRIX WHICH INTERNAL VARIABLE IS THE MEAN DISLOCATION DENSITY ON A SLIP SYSTEM. THIS MODELISATION IS ABLE TIO REPRODUCE THE BEHAVIOR OF FERRITE AND IRON-SILICIUM SINGLE CRYSTALS FOR SIMPLE AND COMPLEX LOADING PATHS. IN A SECOND TIME, THE SCALE TRANSITION BETWEEN THE LOCAL BEHAVIOR AND THE ONE OF A POLYCRYSTALLINE AGGREGATE IS REALIZED THANKS TO THE SELF-CONSISTENT SCHEME AT THE SENSE OF HILL. IT IS SHOWN THAT, AT THIS STEP, THE ADOPTED MODEL IS ABLE TO PREDICT THE BEHAVIOR FOR SINGLE-PHASE, DUAL-PHASE FERRITE AND MARTENSITE AND SINGLE-PHASE WITH PRECIPITATES STEELS FOR SIMPLE AND COMPLEX LOADING PATHS. IN PLUS, THIS MODEL GIVES ALSO GOOD RESULTS FOR CALCULUS OF LANKFORD COEFFICIENT AND YIELD SURFACE AND ALSO FOR PREDICTING TEXTURE EVOLUTION. THE THIRD STEP CONISTS IN THE INTRODUCTION OF A DUCTILITY LOSS CRITERION BASED ON THE ELLIPTICITY LOSS OF THE ELASTIC-PLASTIC TANGENT MODULUS, THIS IS RICE'S CRITERION. THIS CRITERION IS USED TO PLOT FORMING LIMIT DIAGRAMS AND IT IS SHOWN THAT GOOD RESULTS CAN BE GIVEN.
Document type :
Theses
Complete list of metadatas

https://pastel.archives-ouvertes.fr/pastel-00001207
Contributor : Ecole Arts Et Métiers Paristech <>
Submitted on : Friday, April 22, 2005 - 8:00:00 AM
Last modification on : Friday, April 22, 2005 - 8:00:00 AM
Long-term archiving on: : Thursday, September 30, 2010 - 6:28:21 PM

Identifiers

  • HAL Id : pastel-00001207, version 1

Collections

Citation

Jean-Paul Lorrain. Ductility criterion based on ellipticity loss of the elastic-plastic tangent modulus deduced from a self consistent model. Engineering Sciences [physics]. Arts et Métiers ParisTech, 2005. English. ⟨NNT : 2005ENAM0002⟩. ⟨pastel-00001207⟩

Share

Metrics

Record views

388

Files downloads

272