Pickering, corrosion

Langenegger, E. E. and Robinson, F. P. A., Effect of the Polarisation Technique on Dezincihcation Rates and Physical Structure of Dezincihed Zones , Corrosion, 24, 411 (1968) Brooks, W. B., Discussion of the De-alloying Phenomenon , Corrosion, 24, 171 (1968) Pickering, H. W., Volume Diffusion During Anodic Dissolution of a Binary Alloy , J. Electrochem. Soc., 115, 143 (1968)... 

Fig. 8.3 Schematic representation of the stress corrosion cracking mechanism of the pit (after Pickering and Swann ). (a) Tubular pits initiated at solute-rich slip step. The pits may, but need not necessarily, follow the slip plane once they are initiated, (b) Ductile tearing along a plane containing the tubular pits. The stress is increased across the plane because of the reduced cross section and the stress raising effect...

H.W. Pickering, A Critical Review of IR Drops and Electrode Potentials within Pits, Crevices and Cracks, Advances in Localized Corrosion NACE 9, H.S. Isaacs, U. Bertocci, J. Kruger, and S. Smialowska, Ed., National Association of Corrosion Engineers, 1990, p 77-84... 

Pickering and coworkers [31, 34, 35] have demonstrated both experimentally and computationally that for systems that meet the criteria of the IR theory, lA is predicted. The amount of potential drop increases as one moves into the crevice because of the current leaving the crevice. If the geometry, solution conductivity, and passive current density of the material in the environment conspire to create sufficient ohmic drop, then the potential of some portion of the material within the crevice falls to the primary passive potential. Under these circumstances, the passive film is not stable and active dissolution occurs. The potential difference between the applied potential and the primary passivation potential is referred to as IR. Deeper still into the crevice the ohmic drop leads to decreased dissolution as the overpotential for the anodic reaction decreases. Thus, ohmic drop is responsible for the initiation and stabihzation of crevice corrosion according to this model. 

A major barrier to the quantitative understanding of crevice corrosion has been the difficulty in producing crevices experimentally that can be modeled computationally. Pickering and coworkers [42-44] have overcome this barrier at the millimeter scale in their studies of Ni in sulfuric acid. 

M. I. Abdulsalam, H. W. Pickering, The effect of crevice-opening dimension on the stability of crevice corrosion for nickel in sulfuric acid, J. Electrochem. Soc. 145 (1998) 2276-2284. 

H. Shu, F.M. Al-Faqeerb, H.W. Pickering, Pitting on the crevice wall prior to crevice corrosion iron in sulfate/chromate solution, Electrochim. Acta 56 (2011) 1719—1728. 

A.M. Al-Zahrani, H.W. Pickering, IR voltage switch in delayed crevice corrosion and active peak formation detected using a repassivation-type scan, Electrochim. Acta 50 (2005) 3420—3435. 

Fliz, J., Sehgal, D.L., Kho Y-T, Sabotl, S., Pickering, H., Osseo-Assare, K. and Cady, P.D. (1992). Condition Evaluation of Concrete Bridges Relative to Reinforcement Corrosion. Volume 2 Method for Measuring the Corrosion Rate of Reinforcing Steel. National Research Council. Washington, DC. SHRP-S-324. 

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