A computational study of hydrogen embrittlement phenomena in an iron nickel based alloy

Authors
Simonetti, Sandra Isabel; Brizuela, Graciela Petra; Juan, Alfredo
Publication Year
2009
Language
English
Format
article
Status
Published version
Description
The interaction between H atoms and a Fe50Ni50 alloy containing vacancies was studied. The energy of the system was calculated by the atom superposition and electron delocalization molecular orbital (ASED-MO) method. The electronic structure was studied using the concept of density of states (DOS) and crystal orbital overlap population (COOP) curves. The minimum energy position for the H atom in the vacancy region was found at 1.32 Å from the vacancy centre. The changes in the electronic structure of Fe and Ni atoms near the vacancies were analyzed. The interactions mainly involve Fe and Ni metal 4s and 4p atomic orbitals, the most important being the contribution of Fe orbitals. Fe–Fe, Fe–Ni and Ni–Ni bonds weakened as new Fe–H ones were formed. The effect of H atoms is limited to its first neighbours. The detrimental effect of H atoms on the metallic bonds can be related to the mechanism for H embrittlement.
Fil: Simonetti, Sandra Isabel. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina
Fil: Brizuela, Graciela Petra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina
Fil: Juan, Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina
Subject
VACANCY
ALLOY
HYDROGEN
EMBRITTLEMENT
Física Atómica, Molecular y Química
Ciencias Físicas
CIENCIAS NATURALES Y EXACTAS
Access level
Open access
License
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/69944