Measurement of corrosion potential is a relatively simple concept, an unanimously accepted notion in industry for the monitorization of steel corrosion, in building industry and in other structures. Equally, in the last decades, this parameter has been intensively utilized for characterizing dental alloys in either natural oral environment or in simulated solutions. The corrosion potential may be measured directly versus a reference electrode, characterized by a highly stable semi-cell potential. In this respect, a reference electrode (or a separated sensor of the material to be monitorized) is introduced in the corrosive medium together with the metal or alloy under study, and the potential is measured directly with a millivoltmeter with very high input impedance. Additional details on the processes occurring
in the system may be acquired if analyzing the curves of cyclic polarization, for whose obtaining the potential of the electrode formed with the investigated alloy is increased, at constant rate, in positive direction, up to a pre-established value, followed by its scavenging in reverse direction (towards negative values) until reaching the initial value or some other value. During scavenging of the potential, the electric power passing through the solution between the working electrode and an auxilliary (platinum-made) electrode is measured.
- corrosion
- nickel.
- polarization