Title :

The role of emerging grain boundary at iron surface, temperature and hydrogen on metal dusting initiation

Author(s) :

Bentria, El Tayeb [Auteur]
Qatar Environment and Energy Research Institute [QEERI]
N'tsouaglo, Gawonou K. [Auteur]
Qatar Environment and Energy Research Institute [QEERI]
Becquart, Charlotte [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Bouhali, Othmane [Auteur]
Texas A&M University at Qatar
Mousseau, Normand [Auteur]
Université de Montréal [UdeM]
El-Mellouhi, Fedwa [Auteur]
Qatar Environment and Energy Research Institute [QEERI]

Journal title :

Acta Materialia

Volume number :

135

Pages :

340-347

Publication date :

2017-08-15

ISSN :

1359-6454

HAL domain(s) :

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

English abstract : [en]

We conduct a multiscale modeling of different iron systems exposed to carbon-rich atmospheres by means of density functional theory and reactive molecular dynamics in order to evaluate the effects of temperature, gas content ...
Show more >We conduct a multiscale modeling of different iron systems exposed to carbon-rich atmospheres by means of density functional theory and reactive molecular dynamics in order to evaluate the effects of temperature, gas content and surface defects such as emerging grain boundaries and grooves on CO dissociation rate. Comparative density functional theory calculations of carbon adsorption energies on clean surface and the groove area show that grooves have preferential binding sites, explaining why emerging grain boundaries are more severely attacked by metal dusting corrosion. Molecular dynamical simulations using a ReaxFF potential on iron Σ3 and Σ5 emerging grain boundaries on (111) and (210) surfaces, respectively, also demonstrate the enhanced CO dissociation rate within the grooves area. Analysis of CO dissociation and recombination events on these systems demonstrates quantitatively the dual role of hydrogen as a CO dissociation enhancer and reactant with dissociated carbon atoms. By carefully characterizing reaction mechanisms as a function of reactant content, we provide a linear correspondence between CO dissociation variation as function of temperature and the experimental measurement of metal dusting corrosion rate.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
ENSCL
CNRS
INRA

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Métallurgie Physique et Génie des Matériaux

Submission date :

2019-05-16T17:20:55Z
2021-06-17T15:19:09Z
2024-04-16T13:37:44Z