The quantity of polarization is determined by?

The quantity of polarization in cathodic protection is primarily determined by the off-native structure to electrolyte potential. This refers to the difference in electrical potential between the metal surface and the electrolyte surrounding it when the protective potential is measured. When a structure such as a pipeline is placed in an electrolyte, various electrochemical reactions occur, which can cause the potential of that structure to shift.

The off-native potential indicates how much polarization exists as a result of these reactions and the external factors influencing them. Measuring this potential helps assess the effectiveness of the cathodic protection system in preventing corrosion.

While temperature variations, current density, and metal composition can influence impedance and the overall behavior of the cathodic protection systems, they are not direct measures of polarization itself. Instead, they serve as factors that can affect the dynamics of the electrochemical processes occurring at the interface between the metal and the electrolyte. Understanding off-native potential is crucial for evaluating protection levels and making adjustments to the cathodic protection strategy as needed.