Corrosion thermodynamics

The thermodynamics of corrosion processes provides a tool to determine the theoretical tendency of metals to corrode. Thus, the role of corrosion thermodynamics is to determine the conditions under which the corrosion occurs and how to prevent corrosion at the metal/environment interface. Thermodynamics, however, cannot be used to predict the rate at which the corrosion reaction will proceed [1—6]. The corrosion rate must be estimated by Faraday s law and is controlled by the kinetics of the electrochemical reaction. 

The energy change of the partial corrosion reactions provides the driving force for the overall reaction and controls its spontaneous direction. Corrosion thermodynamics... 

The corrosion potential can be easily measured by recording the potential difference between a corroding electrode and a stable reference electrode. It can be used in conjunction with Pourbaix diagrams as a basic indicator of corrosion thermodynamic status, such as active, passive or immune behavior with and without the presence of corrosion inhibitors. Corrosion potential monitoring is often useful in understanding the effects of a corrosion inhibitor on corrosion thermodynamics. Unfortunately, like any thermodynamic quantity, the potential value on its own does not provide information on the rate of corrosion. 

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