Journal Article

IMPULSE-2025-00004

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Influence of hydrogen on the γ-matrix lattice parameters of a Ni-based superalloy – A synchrotron diffraction study

Fritton, M. (Corresponding author)MLZ* ; Mutschke, A.MLZ* ; Nagel, O. ; Stark, A. ; Hafez-Haghighat, M. ; Gehrmann, B. ; Neumeier, S. ; Gilles, R.

2025
Elsevier Lausanne

Please use a persistent id in citations: doi:10.1016/j.jallcom.2025.178693

Abstract: Hydrogen, as an energy carrier, is expected to play a significant role in future mobility. The objective of thisstudy was to investigate the hydrogen uptake of the Ni-based superalloy VDM® Alloy 780 through electrochemicalcharging, using high-energy synchrotron X-ray diffraction (HEXRD). It is shown that the incorporationof hydrogen at interstitial positions in the crystal lattice leads to a slight increase in the lattice parameterscompared to hydrogen-free analogs. In-situ HEXRD measurements showed a convergence of the lattice parametersat elevated temperatures, indicating the reversibility of hydrogenation through diffusion and subsequenteffusion of hydrogen. Hot gas extraction (HGE) measurements were conducted to quantify hydrogen and complementthe diffraction data, showing that prolonged electrochemical charging leads to increased hydrogencontent. Hydrogen quantification at different temperatures confirmed increasing diffusion with temperature, i.e.higher measured hydrogen values at elevated temperatures. Additionally, tensile tests were conducted to evaluatethe influence of hydrogen on the alloy during deformation. Fractographic analysis via SEM showed that, forthe hydrogen-treated specimen, cleavage fracture occurred in the vicinity of the surface, whereas the referencesample displayed typical ductile fracture patterns over the entire fracture surface.1. IntroductionTo move away from the dependency on fossil fuels and achievecarbon neutrality, hydrogen has been singled out as a key technology.Hydrogen-based energy infrastructure may help in evolving our energysystems by providing an unlimited reservoir and enabling emission-freecombustion to reduce CO2 pollution. Hydrogen can serve as an energycarrier or as a feedstock. Furthermore, hydrogen can be used to storeseasonal fluctuating amounts of renewable electricity. The use ofhydrogen as a fuel in jet engines or gas turbines is, however, an ambitiousgoal. One particular problem could be the failure of componentsdue to hydrogen embrittlement (HE), which has been observed invarious industrial systems, including high-pressure hydrogen storagetanks or pipelines. This could occur in aircraft components as well,which are made of high-strength nickel-based superalloys or stainlesssteel [1–3]. HE of alloys and its underlying mechanisms remains a majorchallenge for material science and will become even more importantwith the surging use of hydrogen as an energy carrier. Materials subjected

Keyword(s): Engineering, Industrial Materials and Processing (1st) ; Materials Science (2nd)

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Contributing Institute(s):

1. ADVMAT (ADVMAT)

Research Program(s):

1. 05K22WO3 - Verbundprojekt 05K2022 - H2Mat: Ein Gerät zur Untersuchung des Einflusses der Wasserstoffbe- und -entladung für industriell entwickelte und verwendete Legierungen. Teilprojekt 1. (BMBF-05K22WO3) (BMBF-05K22WO3)

Experiment(s):

1. No specific instrument

Appears in the scientific report 2025

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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