The initial stage of salt passivation of metals

A theoretical model of the nucleation of a passivating salt layer on the surface S of an anode-dissolving metal was developed. The layer is considered a new phase formed by the mechanism of heterogeneous nucleation, which serves as a related substrate for subsequent growth of the passivating layer. According to experiments, the surface S of real metals is inhomogeneous, that is, anode current density fluctuates on S. It is assumed that, at large current fluctuations, localized regions with volume ΔV φ appear, in which the C M and C A concentrations of the M z+ and A n- ions are increased. At fairly large current fluctuations, these concentrations can reach saturation. For this reason, the ΔV φ regions are treated as mother phases, in which A a M m salt nuclei are formed with a certain probability. The formation of such ΔV φ volumes and the kinetics of formation of nuclei in them, from which a passivating layer with a finite thickness is formed, are considered. © 2010 Pleiades Publishing, Ltd.

Number of issue
12
Language
English
Pages
2143-2147
Status
Published
Volume
84
Year
2010
Organizations
  • 1 Karpov Research Institute of Physical Chemistry, Ul. Vorontsovo pole 10, Moscow 105064, Russian Federation
  • 2 Peoples Friendship University, Ul. Miklukho-Maklaya 6, Moscow 117198, Russian Federation
Keywords
Anode current density; Finite thickness; Heterogeneous nucleation; Initial stages; Large current; Passivating layer; Real metals; Salt layers; Theoretical models; Nucleation; Passivation
Date of creation
19.10.2018
Date of change
19.10.2018
Short link
https://repository.rudn.ru/en/records/article/record/2658/
Share

Other records

Abdallah S., Emukule G., Luchters S., Kingola N., Barasa M., Mucheke S., Mwarogo P., Tegang S.-P.
Sahara J. Vol. 7. 2010. P. 10-16