Hydrogen Isotope Effect in Embrittlement and Fatigue Crack Growth of Steel

Published

March 7, 2019

Author(s)

Matthew J. Connolly, Andrew J. Slifka, Robert L. Amaro, Elizabeth S. Drexler, May L. Martin

Abstract

The corrosive effect of hydrogen on steel is a long-standing problem. Corrosion in the presence of hydrogen is, in part, a consequence of the fast diffusion of hydrogen in ferritic steels. Because of the identical chemical properties but large differences in mass between hydrogen isotopes, interaction of hydrogen isotopes with steel structures are of interest as a tool to study the role of diffusion in hydrogen corrosion under \textit{ceteris paribus} conditions. In this paper, we present tensile and fatigue data for steel specimens measured in air, in hydrogen, and in deuterium. Tensile measurements show deuterium causes a loss of ductility comparable to the loss due to hydrogen. In fatigue, a large pressure effect on deuterium- assisted fatigue crack growth was observed, which is not exhibited in hydrogen-assisted fatigue crack growth. With sufficient pressure for enhanced, deuterium-assisted fatigue crack growth is well-predicted assuming a scaling of the diffusion coefficient by $1/\sqrt{2}$. These results suggest surface adsorption kinetics play a large role in hydrogen-assisted fatigue crack growth at low pressure. At higher pressures, hydrogen-assisted fatigue crack growth is primarily affected by kinetics of the diffusion of hydrogen within the lattice.

Citation

Materials Science and Engineering A

Pub Type

Journals

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DOI Link

Keywords

Fatigue, Deuterium, Hydrogen environment assisted cracking

Citation

Connolly, M. , Slifka, A. , Amaro, R. , Drexler, E. and Martin, M. (2019), Hydrogen Isotope Effect in Embrittlement and Fatigue Crack Growth of Steel, Materials Science and Engineering A, [online], https://doi.org/10.1016/j.msea.2019.03.038 (Accessed April 29, 2024)