Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 49: Structural Materials (Steels, light-weight materials, high-temperature materials) - I
MM 49.1: Vortrag
Donnerstag, 19. März 2020, 10:15–10:30, BAR 205
First principles study on hydrogen behaviour in Cr and Mn containing carbides of high Mn steels — •Lekshmi Sreekala, Tilmann Hickel, and Jörg Neugebauer — Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237, Düsseldorf
Understanding hydrogen-assisted embrittlement of advanced high- strength steels is decisive for their application in automotive industry. Since the addition of Cr to the composition of high-Mn steels improves their corrosion resistance and simultaneously changes the microstructure, the influence of Cr and Mn on hydrogen solubility in the context of carbide formation is scientifically challenging. Density functional theory based calculations have been employed to determine the thermodynamic driving force for the formation of carbides as a function of the chemical composition of the alloy and also to study hydrogen interaction of carbides and interfaces containing Cr and Mn. Our results show that Cr has an indirect impact on hydrogen, since it strongly influences the thermal stability of the carbides like cementite and Fe23C6. However, the individual Cr atom interacts only weakly with H. On the other hand, Mn has a weaker impact on carbide formation. However, its incorporation into the carbides yields a remarkably strong non-linear interaction with hydrogen, qualitatively different from the known H-Mn interaction in the austenitic steel matrix.