Abstract
Keywords:
EIS, Porosity, Water uptake, Delamination area, Pulsed potentiostatic test
Abstract
Until now, many accelerating tests, such as salt spray test and cyclic corrosion test, for evaluating the corrosion performance have been suggested. These tests have the advantage of short period in performing the corrosion test in simulating the outdoor environments. To complement the gap between accelerated laboratory corrosion testing and real world corrosion behavior, the modification was designed to simulate corrosion under conditions of exposure of the coatings. The performance of coatings in our laboratory tests was evaluated in terms of experimental assessment for development of accelerated corrosion test using electrochemical techniques such as potentiodynamic polarization test, potentiostatic test and electrochemical impedance spectroscopy (EIS). In order to keep the comparisons consistent at all data of evaluation in the test, only the pulsed potentiostatic test which consists of anodic potential and cathodic potential was used. The anodic potential and cathodic potential was found to be suitable for simulating mechanical and cathodic delamination, respectively. At the end of the pulsed potentiostatic test, degree of corrosion was evaluated using EIS methods. Based on these results it is concluded that pulsed potentiostatic test is a reliable method and should be recommend. This paper presents the progress of an ongoing corrosion performance of underbody parts for automotive and correlation between the field test and the accelerated corrosion test using electrochemical techniques.