Abstract
The influence exerted on the evaluation and meaning of the polarization resistance by the distribution of the current density over the surface of the working electrode is examined and a mathematical expression, which allows an accurate treatment of this problem, is suggested. The criterion, that should be adopted to obtain reliable information about the corrosion rate through the use of the linear response and verify the presence of the Tafel behaviour in the geometric shape of the polarization curves of the electrochemical systems, is also discussed.
A brief description of the SOFTCOR-DC-GDC program, which performs electrochemical measurements using the galvanostatic mode and a current ramp, illustrates the outstanding features of our methodology developed to carry out polarization curves on rebars embedded in the concrete matrix when their corrosion resistance is very high.
Some considerations on the advisability of developing software for scientific applications lead to a deeper reflection on the importance of measurement techniques and the meaning of experimental data.
Experimental results were very satisfactory and confirmed the validity of our approach, but cannot by themselves explain the kinetics of the overall process. This is a direct consequence of the limitation of the linear polarization method and the complexity of the electrochemical reactions.
