Pitting potential measurement

Seys, A. A. and van Haute, A. A., Pitting Potential Measurements by the Static Potential Band Method , Philipp. Geogr. J., 16, 107 (1972) C.A., 79, 99726g Pourbaix, M., Signilicance of Protection Potential in Pitting, Intergranular Corrosion and Stress-corrosion Cracking , J. Less-common Metals, 28, 51 (1972)... 

Seys, A. A. and Van Haute, A. A., Pitting Potential Measurements by Means of the Static Potential Band Method , Corrosion, 29, 329 (1973)... 

As shown in Fig. 25, an example of the extrapolation of the current transient obtained from the potential sweep yields the critical potential after ascertaining that the data obtained are independent of the sweep rate. Figure 26 exhibits the results of the critical pitting potential measurement for the majority salt of NaCl and the minority ion of Ni2+when the concentration of NaCl is varied under the condition of constant Ni2+ionic concentration. From the plot in Fig. 26, it follows that... 

Internal condition of pipes can be assessed through visual inspection photomicrographs, weight loss, pitting potential measurements, scale analysis, and corrosion probe data. From the corrosion data, service life of the pipes can be estimated. 

Because pitting exhibits probabilistic behavior, the induction time T (the time for the occurrence of the first pit) in potentiostatic conditions is a probabilistic value and here the model described above does not hold. In the same way, the pitting potential measured in potentiokinetic conditions is probabilistic. 

Figure 16 shows the efifect of aging the samples for 24 h at rest potential before the pitting potential measurement in NaCl (0.02 M), pH 6.6, instead of for 15 min in the standard procedure. The rest potential evolution was recorded and found to be... 

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