Title :

Molecular dynamics simulation-based study of creep–ratcheting behavior of nanocrystalline aluminum

Author(s) :

Babu, Pokula Narendra [Auteur]
Becquart, Charlotte [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Pal, Snehanshu [Auteur]

Journal title :

Applied Nanoscience

Abbreviated title :

Appl Nanosci

Publisher :

Springer Science and Business Media LLC

Publication date :

2020-11-01

ISSN :

2190-5517

HAL domain(s) :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]

English abstract : [en]

In the present study, molecular dynamics simulations have been performed to investigate the creep–ratcheting deformation behavior of nanocrystalline aluminum (NC Al) having an average grain size of ~ 8 nm. The influence ...
Show more >In the present study, molecular dynamics simulations have been performed to investigate the creep–ratcheting deformation behavior of nanocrystalline aluminum (NC Al) having an average grain size of ~ 8 nm. The influence of deformation temperature on creep–ratcheting behavior has been studied and associated with underlying mechanisms based on the structural evolution of the material identified. The vacancy concentrations, strains and dislocation densities have been evaluated at the end of each stage of creep–ratcheting process for two ratcheting stress ratios and three different temperatures. In the mean time, the microstructural and defect evolution has been investigated. Accumulation of creep–ratcheting strain is found to increase with the deformation temperature in the range of temperature investigated: 10–467 K. Cyclic hardening dominates in the initial stages of creep–ratcheting, whereas cyclic softening dominates in the final stages at a higher temperature. The creep–ratcheting plots exhibit a primary and steady state regions at room temperature (300 K). In addition, a tertiary region is also perceived at high temperature (467 K). The NC Al specimen is also found to be damaged earlier at a higher temperature (i.e., 467 K) than at 10 K and 300 K. The highest dislocation density is attained for room temperature creep–ratcheting deformation. Finally, it is seen from the dislocation analysis that the Shockley partial and full dislocations are the driving dislocations for the creep–ratcheting deformation process.Show less >

Language :

Anglais

Audience :

Internationale

Administrative institution(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Métallurgie Physique et Génie des Matériaux

Submission date :

2020-11-02T15:32:57Z
2020-11-07T21:07:00Z
2020-11-16T09:10:01Z
2020-11-16T09:18:11Z