Atomistic simulations of hydrogen distribution in Fe–C steels. (5th September 2022)

• Record Type: Journal Article
• Authors: Nowak, C.; Sills, R.B.; Ronevich, J.A.; San Marchi, C.W.; Zhou, X.W.
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 76(2022)
• Page Start: 32732
• Page End: 32740
• Publication Date: 2022-09-05
• Subjects: Hydrogen embrittlement -- Fe–C steels -- Molecular dynamics -- Thermodynamics and kinetics -- Diffusion -- Arrhenius behavior; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.07.166
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: To engineer low-cost Fe–C based steels for application in hydrogen energy technologies, an understanding of the hydrogen distribution inside the material and how it is affected by the microstructure is vital. Molecular statics and molecular dynamics simulations are used to study hydrogen distribution and transport kinetics in the ferritic and martensitic phases of Fe–C steels, with and without dislocations present. We find that hydrogen preferentially resides in martensite especially in high dislocation density regions near the martensite/ferrite boundaries, in agreement with experiments. Furthermore, the rate of hydrogen transport through ferrite is up to an order of magnitude greater than that in martensite. The fundamental mechanisms behind this phenomenon are analyzed. Highlights: H solubility model between steel phases across dislocation densities is established. H diffusion near dislocations in ferrite and martensite is calculated with MD. Experimental observations differences in H flux explained using Molecular Dynamics.