Improved Tafel-Based Potentiostatic Approach for Corrosion Rate Monitoring of Reinforcing Steel

Abstract

Potential step voltammetry (PSV) was introduced in earlier works as an advantageous alternative to traditional methods for measuring corrosion rate in reinforced concrete. The present study aims to improve PSV to maximize its applicability in corrosion rate monitoring, that is, beyond the narrowly-defined steel–concrete systems in which was initially validated. It was therefore identified necessary to address the most suitable PSV pulse amplitudes to accurately obtain the Tafel lines and, therefore, corrosion rate in steel-mortar systems with well-differentiated ohmic drop. PSV findings were compared to reference methods, i.e. Tafel intersection and linear polarization resistance. As a novelty, we propose a procedure to improve the reliability of the PSV-determined Tafel lines, which is based on three protocols (P1, P2 and P3). P1 consists of a specific pulse sequence to accurately characterize the morphology of the polarization curve without disturbing the system. P2 consists of two short pulses for determining the ohmic drop compensation factor. Finally, P3 consists of a simple calculation procedure to accurately adjust the PSV pulse amplitudes (∆V) to the steel–concrete system assessed, thus obviating the need for preset values and, therefore, ensuring accurate corrosion rate results. The procedure proposed is intended to improve PSV with a view to its consolidation as a reliable tool for the unsupervised monitoring of real structures.

Effects of Film Thickness of ALD-Deposited Al2O3, ZrO2 and HfO2 Nano-Layers on the Corrosion Resistance of Ti(N,O)-Coated Stainless Steel

“…The calculated values of the cathode and anode slope were all high. However, for the bare SS support, the cathodic slope was significantly higher than the anodic one, indicating a cathodic reduction detrimental to the anodic oxidation [58][59][60]. In the case of SS/Ti(N,O) coatings, the slopes were quite similar, such that it may be concluded that the hydrogen evolution and metal dissolution were almost in equilibrium [61].…”

OC, HPC, UHPC and UHPFRC Corrosion Performance in the Marine Environment

“…During the exposure period, the corrosion rate was periodically measured in each rebar using the potentiostatic step voltammetry (PSV) technique. This technique has been described and validated in previous works [127][128][129][130]. It allows for rebar corrosion analysis by studying the response of steel to potentiostatic-type disturbance.…”

Influence of Starch Admixtures and Silver Colloids Stabilised with Starch Hydrolysates on the Course of Electrochemical Potential Difference of Reinforcing Steel in High-chloride Environment

“…These include the following: Due to the electrochemical nature of the corrosion processes that occur in reinforced concrete structures, several methods are used for diagnostic tests. They determine the probability of corrosion in reinforcement (that is, measurement of stationary potential and resistivity of concrete cover) or the rate of corrosion progress in reinforcement (that is, polarisation method) [3,[28][29][30].…”