Spatiotemporally Resolved Corrosion Inhibition Studies of Lithium Salts for Aerospace Aluminium Alloys

Over many decades, intensive studies have been performed towards safe and sustainable substitutes for chromate corrosion inhibitors in active corrosion protection coatings for aerospace aluminium alloys. The proposed candidates must provide similar corrosion protection as compared to that of chromate-based compounds and be cost-effective for...

Corrosion classification through deep learning of electrochemical noise time-frequency transient information

This paper for the first time treats the interpretation of electrochemical noise time-frequency spectra as an image classification problem. It investigates the application of a convolutional neural network (CNN) for deep learning image classification of electrochemical noise time-frequency transient information. Representative slices of these...

Spatiotemporally resolved corrosion protection of AA2024-T3 by a lithium-based conversion layer

In this work, the corrosion mechanism of AA2024-T3 covered by a lithium-based conversion layer is studied with high spatial and temporal resolution. Although the aluminium alloy surface is protected by a multi-layered conversion layer, areas around intermetallic phases (IMPs) represent weak spots due to an insufficient generation of a...

Atmospheric corrosion of iron under a single droplet: A new systematic multi-electrochemical approach

Utilizing a dedicated micro-sized three-electrode cell, this study systematically investigates early-stage electrochemical properties and corrosion behavior of pure iron under single droplets. Various volumes and NaCl concentrations were considered during the evaporation-driven shape and concentration evolution of single droplets. The...

The Effect of Ambient Ageing on the Corrosion Protective Properties of a Lithium-Based Conversion Layer

The influence of ageing under ambient conditions on the corrosion protective behaviour of a lithium-based conversion layer on AA2024-T3 is studied in this work. Conversion layers aged at ambient conditions for relatively short times (0 h and 4 h), show an initial high degree of corrosion inhibition but a much lower protectiveness after the...

An integral non-intrusive electrochemical and in-situ optical technique for the study of the effectiveness of corrosion inhibition

This work investigates an integrated analysis of in-situ optical data and time-frequency information from electrochemical potential noise (EPN) data to study the effectiveness and durability of an anodic and cathodic corrosion inhibitor. Two different corrosion inhibiting species, cerium(III) (Ce(III)) and phytic acid (PHA), are tested on...

Evaluation of the formation and protectiveness of a lithium-based conversion layer using electrochemical noise

The formation process of a lithium-based conversion layer on AA2024-T3 and its corrosion protective behavior are studied using electrochemical noise (EN). Wavelet transform, as well as noise resistance analysis, have been employed to interpret the EN data. The EN data confirmed five different stages during the conversion layer growth,...

Wavelet transform modulus maxima and holder exponents combined with transient detection for the differentiation of pitting corrosion using electrochemical noise

A potentially powerful tool to detect and classify corrosion mechanisms is the analysis of electrochemical noise (EN). Data analysis in the time-frequency domain using, e.g., continuous wavelet transform (CWT) allows the extraction of localized frequency information, providing information on the type of corrosion, i.e., uniform or localized...

Electrochemical Noise: A Clear Corrosion Signature

The interpretation of electrochemical noise (EN) data has long been under discussion. Throughout the years, many data analysis techniques have been proposed for this purpose. As a starting point, procedures and parameters that enable identification of, or discrimination between, general and localized corrosion processes through EN are critically...