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Ultrathin Hydrogen Diffusion Cloak
Advanced Theory and Simulations, 2017AbstractFor years, hydrogen damage is a fatal threat to metals and alloys in long‐term service. This paper introduces the transformation optics theory in metamaterials to the diffusive field, and the design of an ultrathin hydrogen diffusion cloak. Thanks to the alternately and gradually changed diffusion coefficients in adjacent layers, the laminated ...
Yang Li +4 more
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Nature, 1967
HYDROGEN isotope diffusion in metals and polymers has generally been treated in the literature as a single body problem with the motion of the hydrogen regarded as the important parameter. On this basis the equation for interstitial diffusion of hydrogen atoms in metals or molecular diffusion in polymers follows an equation of the form
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HYDROGEN isotope diffusion in metals and polymers has generally been treated in the literature as a single body problem with the motion of the hydrogen regarded as the important parameter. On this basis the equation for interstitial diffusion of hydrogen atoms in metals or molecular diffusion in polymers follows an equation of the form
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Hydrogen diffusion in tantalum
Physics Letters A, 1988Abstract Using the small-polaron theory of diffusion we obtain a very good fit of the experimental data on hydrogen diffusion in tantalum between 15 and 500 K. It is shown that the phenomenon has three regimes: (a) At T > 250 K the transport occurs mainly by hydrogen tunneling between tetrahedral sites. (b) At 200 K >T > 15 K metastable states having
MIRANDA, L +3 more
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?Uphill? hydrogen diffusion effects and hydrogen diffusion coefficients in palladium
International Journal of Hydrogen Energy, 1997Information concerning measurements of hydrogen diffusion coefficients over α- and β-phase ranges of hydrogen content in the palladium/hydrogen system is summarized. The utilization of palladium as a hydrogen purification membrane has constituted a background for observations of “uphill” hydrogen diffusion effects.
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Diffusion of Hydrogen in Hydrogen-Quenched Nickel
Japanese Journal of Applied Physics, 1977The recovery process of hydrogen dissolved in excess in nickel is studied by means of the hydrogen-quenching method which is a modified Schultz's method. Two recovery stages of electrical resistance are found. The lower temperature stage is a new one which presumably arises from trapping and/or clustering of hydrogen atoms in the interior of the ...
Kohji Yamakawa, Francisco Eiichi Fujita
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Hydrogen diffusion in α-Fe2O3: Implication for an effective hydrogen diffusion barrier
International Journal of Hydrogen Energy, 2020Abstract Hydrogen diffusion plays a key role in hydrogen embrittlement which leads to the failure of metals. In the present work, hydrogen diffusions in Fe and α-Fe2O3 were studied by first-principles calculations. The results show the energy barrier of hydrogen diffusion in pure Fe is small and hydrogen atom has a high diffusivity at ambient ...
Baihui Xing +4 more
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2012
This chapter deals with the diffusion properties of hydrogen in zirconium as driven by mass, stress, and thermal gradients. The relevant diffusion equations are derived starting from the phenomenological theory of irreversible thermodynamics. A general expression for the flux of hydrogen in mass (concentration), stress, and temperature gradients is ...
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This chapter deals with the diffusion properties of hydrogen in zirconium as driven by mass, stress, and thermal gradients. The relevant diffusion equations are derived starting from the phenomenological theory of irreversible thermodynamics. A general expression for the flux of hydrogen in mass (concentration), stress, and temperature gradients is ...
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Hydrogen diffusion in aluminum
Scripta Metallurgica, 1983Although the diffusivity of hydrogen in aluminum has been measured by several different authors, there is essentially no mutual agreement and the sets of data are separated by orders of magnitude. There is little doubt these mass-flow determinations of the H-diffusivity are subject to great uncertainties connected with the presence of the surface oxide
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