Potentiodynamic scan

This research established a method to quantify corrosion parameters like potential, current density, and Tafel slopes for rebar in simulated conditions. It examined how depassivation duration, chloride concentration, carbonation, and humidity affect these parameters. Notably, in partially saturated mortar, no distinct threshold was found for critical chloride content, and humidity significantly influenced depassivation indicated by shifts in corrosion parameters.

This dataset provides comprehensive corrosion parameter data for reinforcing steel (rebar) in simulated pore solutions and mortar. It includes detailed measurements of corrosion potential, corrosion current density, and Tafel slopes under various chloride levels and carbonation treatments. The data aims to shed light on the corrosion behaviour of rebar in environments that closely mimic real-world conditions.

This research develops a circuit model to simulate non-uniform rebar corrosion in concrete, revealing that concrete’s resistivity causes non-uniform rebar potential, affecting polarisation curves. This leads to overestimated Tafel constants and corrosion current density, particularly under higher concrete resistivity. Accurate corrosion predictions require potentiodynamic scans or averaging techniques like this model.

A customized Python module for interactive curving fitting in Jupyter Notebook environment right in the browser such as Chrome. It allows users to interactively fit Butler-Volmer equations and its variations to potentiodynamic scan curves. The optimization process is powered by non-linear least squares algorithms from Scipy. It features a user-friendly plotting GUI with Jupyter Notebook widgets. This current release provides options for interactive data range selection, linear/log axis switching, auto-zoomed plotting, and post-IR compensation. The fitted results include corrosion parameters such as corrosion potential, corrosion current, Tafel slopes, polarization resistance, and goodness of fit (R2 score and Chi2 score).

The model initially operates in “open circuit mode” to determine the Open Circuit Potential (OCP). In “scan mode,” it modifies the rebar electrode potential in small steps, within specified scan range bounds, based on the OCP. This potentiodynamic scan process, coded in Python and solved numerically using Scipy’s iterative optimization, improves accuracy by using previous solutions as initial guesses for subsequent steps.