Fundamental Studies on Corrosion of alloys (8th Report). A Consideration on the Hydrogen Overvoltage of Alloys

Abstract

Applying the results of statisco-thermodynamical theory on hydrogen absorption to hydrogen electrode reaction, the author expressed the heat of activation ΔH^* of the alloys which do not form any hydride by the following formula: ΔH^* = f(ρ, T) - αz’ RT lnλ_H^g J_H (N_A/N+N_B/κN)+α(ψ_AH+χ_d/2) where λ_H^g: the absolute activity of H atom in gas phase, J_H: the partition function of H atom, ψ_AH: the interaction energy between A atom in alloy AB and H atom, κ: a term concerned with ψ_AH and ψ_BH. The variation of ΔH^* in iron and copper alloys and the validity of the results of the previous reports were discussed from the formula above mentioned.