Grain-size dependent accommodation due to intragranular distributions of dislocation loops
| Autor: | Marcel Berveiller, Thiebaud Richeton, Stéphane Berbenni |
|---|---|
| Přispěvatelé: | Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM) |
| Rok vydání: | 2009 |
| Předmět: |
Materials science
Polymers and Plastics Metallurgy Metals and Alloys Bauschinger effect [PHYS.MECA]Physics [physics]/Mechanics [physics] 02 engineering and technology Slip (materials science) Mechanics [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] Plasticity 021001 nanoscience & nanotechnology Microstructure Grain size [SPI.MAT]Engineering Sciences [physics]/Materials Electronic Optical and Magnetic Materials 020303 mechanical engineering & transports 0203 mechanical engineering Ceramics and Composites Hardening (metallurgy) Grain boundary Coaxial 0210 nano-technology |
| Zdroj: | Acta Materialia Acta Materialia, Elsevier, 2009, 57 (5), pp.1347-1356. ⟨10.1016/j.actamat.2008.11.024⟩ |
| ISSN: | 1359-6454 |
| DOI: | 10.1016/j.actamat.2008.11.024 |
| Popis: | International audience; A grain-size dependent accommodation law for polycrystals is deduced from an inclusion/matrix problem (i.e., each grain is seen as embedded in a homogeneous equivalent medium) where plastic strain inside the inclusion is given as a discrete distribution of circular coaxial glide dislocation loops. The loops are assumed constrained at spherical grain boundaries. From thermodynamic considerations specific to a process of identical plastification in all the loops (considered as “super-dislocations”), an average back-stress over the grain is derived. In order to compute the very early stages of plastic deformation in a face-centred cubic polycrystal, this back-stress is incorporated into a diluted model in terms of concentration of plastic grains. Contrary to conventional mean-field approaches, a grain-size effect is obtained for the initial overall strain-hardening behaviour. This size effect results from an intrinsic contribution of intragranular slip heterogeneities on the kinematical hardening. |
| Databáze: | OpenAIRE |
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