Application of a new computational method to determine corrosion current density in a cathodically protected system

In the present paper a numerical approach to determine the corrosion current density of a cathodically protected metal is explained. In this method three independent relationships are established and numerical evaluation of the unknowns is carried out by using electrochemical data obtained very close to the protection potential. The results obtained using hypothetical data are shown to be comparable with another method proposed by Meas and Fujioka. The present method, however, has an advantage over this method in that no prior knowledge of the corrosion current density of the unprotected metal (I_c) is required. Because of this restriction, it is shown that the method of Meas and Fujioka is sensitive to slight inaccuracies in the value of I_c used. On the other hand, the present method implicitly calculates the value of I_c.