Validation of a Signal Acquisition for Electrochemical Noise Corrosion Monitoring System

Abstract

Corrosion is a problem that can cause losses up to 4.5% of GDP in industrialized countries besides the environmental impacts. This study proposes a corrosion monitoring system using the passive technique based on electrochemical noise (EN). It measures the natural levels of a corrosion process signal (current or voltage) without any external artificial stimulation. It uses the Zero Resistance Ammeter (ZRA), which allows to galvanically couple two similar working electrodes and measure the current flow at the same time. This approach has the advantage of a simple setup, since there is no need of any signal injection or external stimulus. Due to dynamic and stochastic nature of the signal, this work considers numerical and graphic characteristics of two corrosion systems, carbon steel and stainless steel. The experiments were conducted repeatedly to obtain data for the analysis in time and frequency domains.