Examine the relation between energy and surface potential
Discuss standard potentials in relation to the stability of chemical species
Describe the main reference electrodes used to measure corrosion potential
Explain the features and functions of E-pH (Pourbaix) diagrams
Describe the stability of water, iron, and aluminum from a thermodynamic point of view
This Module consists of seventeen Web pages of required reading. The pagination is visible at the bottom of each page with direct links to adjacent pages.
Additional information can be found in sections 4.1 to 4.8 of the reference textbook (Corrosion Engineering: Principles and Practice).
One can use thermodynamics, e.g. Pourbaix or E-pH diagrams, to evaluate the theoretical activity of a given metal or alloy in a corrosion situation provided the chemical make-up of the environment is known. But for practical situations, it is important to realize that the environment is a variable that can change with time and conditions. It is also important to realize that the environment that actually affects a metal corresponds to the micro-environmental conditions this metal really 'sees', i.e. the local environment at the surface of the metal. (reference)
It is indeed the reactivity of this local environment that will determine the real corrosion damage. Thus, an experiment that would investigate only the nominal environmental condition without consideration for local effects such as flow, pH cells, deposits, and galvanic effects is useless for lifetime prediction.
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See also CCE 513: Corrosion Engineering