Hydrogen permeation effects

Fig. 8.38 Hydrogen permeation current as a function of applied potential, showing effect of change in reaction mechanism below —1200 mV (SCE) (after Obuzor )...

The anode compartment contains a reference electrode and counterelectrode and by means of a potentiostat the anode side is maintained at a constant potential. The coverage of adsorbed hydrogen on the cathode side will depend on the current density i and the nature of the electrolyte solution, and the cell can be used to study the effect of a variety of factors (composition and structure of alloys, pH of solution, effect of promoters and inhibitors) on hydrogen permeation. 

Beck, et al. have used the permeation technique to study the effect of uniaxial tensile stresses in the elastic region on hydrogen permeation through pure iron, and have shown that it increases with increase in stress. The partial molar volume of hydrogen (cubic centimetres of hydrogen per mole of iron) in ferrous alloys can be evaluated from the variation of permeation with applied stress, and from the relationship... 

Shen, J.-N. et al.. Effect of alumina film prepared by pack cementation aluminizing and thermal oxidation treatment of stainless steel on hydrogen permeation, Yuanzineng Kexue Jishu/Atomic Energy Science and Technology, 39, 73 (2005). 

Fukai, T. and K. Matsumoto, Surface modification effects on hydrogen permeation in high-temperature, high-pressure, hydrogen-hydrogen sulfide environments. Corrosion (Houston), 50, 522 (1994). 

Hydrogen permeation testing was conducted using the permeation test rig shown in Figure 2. Samples, 19 mm diameter and 0.89 mm thick or disks were welded into 2.12" diameter Conflat (CF) flanges. Crevices were seal welded using electron beam welding to minimize the effects of virtual leaks. The... 

Jung SH, Kusakabe K, Morooka S, and Kim S-D. Effects of co-existing hydrocarbons on hydrogen permeation through a palladium membrane. J. Membr. Sci. 2000 170 53-60. 

Zhang, Y, Ozald, T, Komald, M, Nishimura, C. Hydrogen permeation of Pd-Ag coated V-15Ni composite membrane effects of overlayer composition. J Membr Sci. 2003 224 81-91. 

Yang, J. Y, Nishimura, C, Komtdd, M. Effect of overlayer composition on hydrogen permeation of Pd-Cu aUoy coated V-15Ni composite membrane. J Membr Sci. 2006 282 337 1. 

Yang, J. Y, Komald, M, Nishimura, C. Effect of overlayer thickness on hydrogen permeation of Pd5oCu4oA -15Ni composite membranes. Int J Hydrogen Eneigy. 2007. doi. 10.1016/j.ijhydene.2006.12.015. 

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