Validation of titanium corrosion impedance data using Kramers-Kronig relationships

In corrosion research the Kramers-Kronig (KK) test of impedance data is a highly valuable tool for data validation. Electrochemical cells in this field of research are often subject to instability and drift, whose conditions seriously and adversely affect the analysis of the impedance spectra. The present paper studies the applicability of KK relationships to assess the validity of real and imaginary corrosion impedance measurements for titanium in a Ringer's solution using the electrochemical impedance spectroscopy (EIS) method. Bode and Nyquist plots showed a capacitive behaviour with a high impedance modulus including two time constants. Two procedures were employed in the implementation of the KK integral relationships based on an equivalent circuit which satisfies KK relationships and an ohmic resistance shunted to the measured EIS data. The titanium's EIS data satisfied the KK relationships.