Electrochemical Studies of Localized Corrosion

There are numerous electrochemical methods to determine the electrochemical conditions of pitting and crevice corrosion. Here we are concerned with pitting corrosion. 

1 Cyclic Potenttodynamic Polarization Method Electrochemical studies of pitting corrosion indicate that pitting occurs within or above a critical potential or potential range. The electrochemical methods involved in pitting corrosion studies are 

Cyclic potentiodynamic polarization used in determining pitting potential consists of scanning the potential to more anodic and protection potentials during the forward and return scans and compare the behavior at different potentials under identical conditions. The polarization curve of an alloy (with or without coating showing active-passive behavior may be obtained in a chosen medium as a function of chloride concentration). E, or Ep represent pitting potential or breakdown potential, 

Methods used to study localized corrosion consist of galvanostatic methods and potentiostatic methods. At constant chosen currents the evolution of potential as a function of time is noted until the rate of change in potential approaches zero. This 

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