corrosion testing accelerated

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Acceleration of Corrosion Damage:

Some of the methods used for accelerating corrosion damage, for the purposes of obtaining test results in a relatively short (reasonable) time frames include the following:

Increasing the temperature to boost corrosion reaction kinetics, as, for example, predicted by the well-known Arrhenius equation. This equation suggests that, as a rule of thumb, for reactions occurring near room temperature, a temperature increase of 10°C approximately doubles the reaction rate. (However, an increase in corrosion rate is not always associated with a temperature increase - consider the formation of corrosive condensate when the temperature is lowered and the decrease in oxygen solubility in water with increasing temperature.)
Applying cyclic temperature ranges.
Acidifying the corrosive medium.
Increasing the corrosivity of the corrosive medium by other chemical changes (e.g. salt concentration, degree of aeration, addition of oxidizing species, etc.).
Alternate wetting and drying (can lead to a surface concentration effect of corrosive species).
Increasing the relative humidity.
Cycling through different humidity ranges/different degrees of moisture exposure.
Application of stress, particularly relevant to stress corrosion cracking tests.
Applying "artificial" currents (and potentials), thereby electrochemically polarizing test specimens.
Applying "artificial" damage to a test surface, e.g. scribing (scratching) a protective coating system.
Creating test geometries that make a specimen more vulnerable to certain forms of corrosion damage, such as setting up artificial crevices.
Combining mechanical degradation (such as erosion, cavitation and impingement) with corrosion damage.

By applying the above acceleration factors, test conditions can obviously be shifted away from actual service environment conditions - with the risk of poor correlations between test and actual service performance.