A Numerical Analysis of Deformation Processes in Oxide Dispersion-Strengthened Materials – Influence of Dislocation-Particle Interactions

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F17%3A00467048" target="_blank" >RIV/68081723:_____/17:00467048 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.4028/www.scientific.net/SSP.258.106" target="_blank" >http://dx.doi.org/10.4028/www.scientific.net/SSP.258.106</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.4028/www.scientific.net/SSP.258.106" target="_blank" >10.4028/www.scientific.net/SSP.258.106</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A Numerical Analysis of Deformation Processes in Oxide Dispersion-Strengthened Materials – Influence of Dislocation-Particle Interactions

Popis výsledku v původním jazyce

A recently developed 3D discrete dislocation dynamics (DDD) model is employed to studynkinetics of dislocation ensembles subjected to high temperature creep in microstructures of metalnmatrix composites. We particularly focus on a migration of low angle tilt boundaries in a field of rigidnimpenetrable particles. This type of dislocation boundaries represents a typical microstructural featurenmediating plastic deformation during the high temperature loadings.nThe article compares results of numerical studies that considered distinct dislocation-particle in-nteractions in order to describe the response of dislocation structure to the applied stress. The resultsnsuggest that, regardless the details related to the dislocation-particle interactions, a critical appliednstress always exists, below which the boundary migration process ceases [1, 2]. The existence of crit-nical threshold is confirmed by creep tests of ODS materials. This critical threshold, contrary to thenclassical Orowan stress, is proportional to the dislocation density. The displacements of individualndislocation segments on the micro-scale level reflect the changes in the dislocation-particle interac-ntions quite sensitively. At the macro-scale level, the overall strain rate, which averages out velocities ofnall the individual dislocation segments, is also significantly influenced by the changes in dislocation-nparticle interaction.

Název v anglickém jazyce

A Numerical Analysis of Deformation Processes in Oxide Dispersion-Strengthened Materials – Influence of Dislocation-Particle Interactions

Popis výsledku anglicky

A recently developed 3D discrete dislocation dynamics (DDD) model is employed to studynkinetics of dislocation ensembles subjected to high temperature creep in microstructures of metalnmatrix composites. We particularly focus on a migration of low angle tilt boundaries in a field of rigidnimpenetrable particles. This type of dislocation boundaries represents a typical microstructural featurenmediating plastic deformation during the high temperature loadings.nThe article compares results of numerical studies that considered distinct dislocation-particle in-nteractions in order to describe the response of dislocation structure to the applied stress. The resultsnsuggest that, regardless the details related to the dislocation-particle interactions, a critical appliednstress always exists, below which the boundary migration process ceases [1, 2]. The existence of crit-nical threshold is confirmed by creep tests of ODS materials. This critical threshold, contrary to thenclassical Orowan stress, is proportional to the dislocation density. The displacements of individualndislocation segments on the micro-scale level reflect the changes in the dislocation-particle interac-ntions quite sensitively. At the macro-scale level, the overall strain rate, which averages out velocities ofnall the individual dislocation segments, is also significantly influenced by the changes in dislocation-nparticle interaction.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Materials Structure & Micromechanics of Fracture VIII

ISBN

978-3-03835-626-4

ISSN

1662-9779

e-ISSN

—

Počet stran výsledku

4

Strana od-do

106-109

Název nakladatele

Trans Tech Publications

Místo vydání

Zürrich

Místo konání akce

Brno

Datum konání akce

27. 6. 2016

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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