FFT analysis of polarization current fluctuation during corrosion fatigue on HT60 high-strength steel

During a potentiostatic corrosion fatigue test, fluctuation of the polarization current which is synchronized with the cyclic tension-compression loading was observed. This current fluctuation means that the corrosion rate was accelerated by the cyclic loading. Using Fourier transformations the authors separated the current component and named it the stress synchronized polarization current (SSPC). A corrosion fatigue test for high tension steel HT60 was carried out in artificial seawater and a borate solution. The result suggests that the SSPC, which can be measured at the early stage of a fatigue test, is useful to estimate the corrosion fatigue damage.