Hydrogen isotope effect on the embrittlement and fatigue crack growth of steel

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:753

Article

Connolly, Matthew¹  Martin, May^1,2  Amaro, Robert³  Slifka, Andrew¹  Drexler, Elizabeth¹ 

[1] Natl Inst Stand & Technol, Appl Chem & Mat Div, Mat Measurement Lab, 325 Broadway, Boulder, CO 80305 USA

[2] Univ Colorado, Dept Phys, Boulder, CO 80309 USA

[3] Southern Res, 2000 Ninth Ave South, Birmingham, AL 35205 USA

关键词: Fatigue;    Hydrogen embrittlement;    Isotope;    Deuterium;    Steel;   

DOI  :  10.1016/j.msea.2019.03.038

来源: Elsevier

【 摘 要 】

The deleterious effect of hydrogen on steel is a long-standing problem. Embrittlement 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 embrittlement under all-else-equal conditions. In this paper, we present tensile and fatigue data for steel samples 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, an effect which is not exhibited in uniaxial tensile measurements, With sufficient pressure to show an enhanced fatigue crack growth effect, the fatigue crack growth rate is well-predicted assuming a scaling of the diffusion coefficient by 1/root 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 the kinetics of diffusion of hydrogen within the steel lattice.

【 授权许可】

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