General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DES-24-0175
Thesis topic details
Category
Engineering science
Thesis topics
Modelling of hydrogen transport and trapping in austenitic steel
Contract
Thèse
Job description
Molecular hydrogen H2 is an alternative energy carrier to traditional fossil fuels, gas or oil. It meet the current energy and environmental challenges, i.e. the need to store greenhouse gases free energy produced by intermittent means such as wind turbines or solar panel. Nevertheless, its safe storage and transportation is one of the keys to its use. The containers or pipes that carry the hydrogen must be leaktight and maintain their integrity over time. Understanding and predicting the behavior of hydrogen in container/pipeline alloys and the associated mechanical degradation – such as embrittlement – is therefore crucial for the development of the hydrogen industry. These issues are also generic to all alloys exposed to a source of hydrogen, in corrosion or in the metallurgical industries where the hydrogen simply comes from contact with water, or in the oil industry where hydrogen comes from hydrogen sulphides present in hydrocarbons – oil or gas.
If many experimental works have identified hydrogen embrittlement as the origin of the degradation of alloys exposed to hydrogen, large gray areas still remain on the mechanisms at work due to experimental difficulties and the great variability of the observed phenomena. In addition, the transport and trapping of hydrogen prior to mechanical degradation are poorly known and poorly documented.
The objective of the thesis is to explore the mechanisms of hydrogen trapping / transport in austenitic materials prior to cracking in order to be able to report and explain the experimental observations.
To achieve this objective, the thesis work will be dedicated to the study of pure nickel, a model system for austenitics. The study will be carried out in two stages: (i) at the atomic scale by molecular dynamics in empirical potentials to obtain detailed information on the transport and the trapping of hydrogen then (ii) at the mesoscopic scale by chemical kinetics modeling coupled with Fick's law that are modified according to the mechanisms identified in molecular dynamics.
University / doctoral school
Sciences Chimiques: Molécules, Matériaux, Instrumentation et Biosystèmes (2MIB)
Paris-Saclay
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2024
Person to be contacted by the applicant
MARTIN Frantz frantz.martin@cea.fr
CEA
DES/DRMP/S2CM/LECA
CEA de Saclay
DEN/ISAS/DRMP/S2CM/LECA
Bat. 458, p. 119
91191 Gif sur Yvette cedex
01 69 08 48 86
Tutor / Responsible thesis director
CHARTIER Alain alain.chartier@cea.fr
CEA
DES/DRMP//LM2T
CEA-Saclay
DEN/DANS/DPC/SCCME/LM2T
bat 450Sud
P.C. 41
91191 Gif-Sur-Yvette
01 6908 3168
En savoir plus
https://www.researchgate.net/profile/Alain-Chartier