Open circuit potential
The free corrosion potential of a metal is the electrical potential at which no corrosion reactions occur in an electrolyte. It represents the voltage at the metal-electrolyte interface that corresponds to the thermodynamic equilibrium state.
Physicochemical Mechanism of Action
The free corrosion potential (E°) of a metal is the potential at which no corrosion reactions occur in an electrolyte. It represents the voltage at the metal-electrolyte interface that corresponds to the thermodynamic equilibrium state.
Metallurgical Relevance & Welding Risks
A lower free corrosion potential means the material is more prone to corrosion. In welded joints, it is important that the metal does not shift to a more corrosive state, as this can shorten the life of the joint.
Workshop Practice & Instructions
When welding, it is important to keep the metal at a stable potential. This can be achieved by choosing the right welding process and correct parameters. If needed, corrosion inhibitors can be used to raise the free corrosion potential and extend the life of the joint.