Leonardo Bertolucci Coelho

Electrochemical nucleation and growth (EN&G) is an inherently dynamic process governed by atomic-level interactions. Understanding the electrochemical phase formation on foreign substrates presents a formidable challenge at the fundamental level. One of the main challenges lies in uncovering both the energetic state of the substrate and the complex...

A hybrid rule-based/ML approach using linear regression and artificial neural networks (ANNs) determined pitting corrosion descriptors from high-throughput data obtained with Scanning Electrochemical Cell Microscopy (SECCM) on 316 L stainless steel. Non-parametric density estimation determined the central tendencies of the E pit /log( jpit ) and E...

Electrochemical nucleation and growth (EN&G) are the cornerstone for many (nano)material growth routes and the main factor limiting battery durability. The in-depth experimental assessment of the process is very challenging due to the random nature of initiation events (nucleation), the heterogeneity of surfaces and the (very) fast kinetics across...

A hybrid rule-base/ML approach using linear regression and artificial neural networks (ANN) determined pitting corrosion descriptors from high-throughput data obtained with Scanning Electrochemical Cell Microscopy (SECCM) on 316L stainless steel. Non-parametric density estimation determined the central tendencies of the E pit /log( jpit ) and E pas...

https://data.mendeley.com/datasets/78rz8vw46x/2 This database comprises 5 Potentiodynamic Polarisation (PP) datasets. Each dataset consists of a pair of CSVs: 1 file containing the values of the applied potential scan rate (mV/s); and 1 having the corresponding current density j (µA/cm²) values.

https://github.com/bcoelho-leonardo/Data-driven-analysis-of-the-local-current-distributions-of-316L-corrosion-in-NaCl-solution/blob/4efff485b115468840b25ea56ad81b31711c0f51/local%20current%20distributions%20of%20316L%20corrosion.ipynb

This work provides a data-oriented overview of the rapidly growing research field covering machine learning (ML) applied to predicting electrochemical corrosion. Our main aim was to determine which ML models have been applied and how well they performed depending on the corrosion topic considered. From an extensive review of corrosion articles pres...

This investigation proposes using Scanning Electrochemical Cell Microscopy (SECCM) as a high throughput tool to collect corrosion activity datasets from randomly probed locations on electropolished 316L SS. In the presence of chloride (varying concentrations), potentiodynamic polarisation tests (varied scan rates) triggered the development of pitti...

Electrochemical nucleation and growth (EN&G) is the cornerstone for many (nano)material growth routes and the main factor limiting battery durability. At the same time electrochemical dissolution (ED) is the main cause of material degradation in exposed environments (corrosion) or energy conversion and storage devices. The in-depth experimental ass...

The effect of Ce(III) on the top surface and galvanic corrosion of ZnFe electrocoated steel was investigated. The inhibition performance was assessed by Electrochemical Impedance Spectroscopy on the surface of the Zn and ZnFe electrodeposited coatings. The ZnFe/steel galvanic coupling was investigated based on a model coupling studied from the pola...

Coolant corrosion inhibitors are paramount for the durability of automotive heat exchangers. The novel generation of “hybrid coolants” consists of inorganic inhibitors added to an OAT (Organic Additive Technology) backbone. This investigation appraises the corrosion inhibition provided by OAT, phosphate and silicate (separately and combined) on AA6...

Different metrics are possible to evaluate the prediction accuracy of regression models. However, only papers providing relative metrics (MAPE, R²) were included in this database. We tried as much as possible to include descriptors of all major ML procedure steps, including data collection (“Data acquisition”), data cleaning feature engineering (“F...

Magnesium is the world's lightest structural metal, with a significant growth potential in view of the accelerating demand for light-weighting portable devices and transportation (aerospace, automotive), amongst other. The effect of carbonate ions on corrosion protection of AZ31 magnesium alloy was studied in 0.1 M NaCl solution saturated in Mg(OH)...

In the present work, a Si/Zr based sol–gel (SG) coating was deposited on 316L stainless steel plates, previously treated by passivation (SSO) or electropolishing (SSEP) producing two different surface states. The SG coatings were compared for SSO and SSEP substrates in terms of morphology, topography and tribocorrosion response. The coating topogra...

A novel experimental approach is proposed for creating surface microdefects in-situ during SVET analysis. Hot-dip galvanized steel samples fixed in the SVET cell and exposed to 0.05 M NaCl were scratched using a Berkovich indenter. The progress of corrosion activity at defect locations was continuously inferred by SVET scan lines starting 10 s afte...

The effect of sodium molybdate in inhibiting galvanic corrosion of Zn coating and mild steel is addressed. The inhibitor's performance was appraised by Zero Resistance Ammeter on HDG/mild steel galvanic coupling model in 0.05 M NaCl (+5 mM Na2MoO4) media. The effectiveness of Na2MoO4 was evaluated on HDG substrate mechanically scratched to reach th...

In suspected cases of COVID-19 infection, the World Health Organization has recommended the thorough cleaning of surfaces and the application of commonly used hospital-level disinfectants are effective procedures. The new virus situation has changed the sanitary habits of industries and this will potentially have anadverse effect on surfaces highly...

This investigation addresses the effect provided by industrial surface finishes on the tribocorrosion properties of 316L stainless steel exposed to NaCl solution. Three distinct surface treatments were evaluated: passivation (SSO), electropolishing-passivation (SSEP) and micro-undulation (SSM mechano-chemical + electropolishing + passivation). For...

The impact of different industrial surface treatments, such as electropolishing and micro-undulation, on the mechanical and corrosion properties of cold-rolled 316L stainless steel has been investigated. The nature of the passive layers created by the three surface finishes led not only to chemical differences as determined by XPS analysis, but als...

Plasma electrolytic oxidation (PEO) coatings were produced on AZ80 magnesium alloy in a solution containing silicates and phosphates and working at high current densities with short treatment times. The effect of a sealing treatment in boiling water on corrosion and mechanical properties of the coatings were investigated. Moreover, the corrosion me...

The corrosion mechanism of an AA2024-T3/Ti6Al4V galvanic couple model (electrodes’ area ratio =1) was investigated in NaCl media by means of Scanning Vibrating Electrode Technique (SVET), Zero Resistance Ammeter (ZRA), potentiodynamic polarisation and Open Circuit Potential (OCP) analysis. Galvanic coupling was not sufficiently intense to impact th...

The inhibition mechanism of cerium chloride and triethanolamine on the galvanic corrosion of AA2024-T3/graphite in NaCl electrolyte was investigated by localised electrochemical techniques. Quasi-simultaneous measurements of ionic current densities and pH were performed by the Scanning Vibrating Electrode Technique (SVET) and Scanning Ion-Selective...

The inhibitive effect brought by benzotriazole (BT) on AA2024 in neutral aerated sodium chloride solutions was evaluated using electrochemical techniques (large and micro scale polarization curves, electrochemical impedance spectroscopy) and surface analyses (ToF-SIMS and XPS) in the view of its incorporation into protective coatings to provide sel...

Electrochemical corrosion is one major cause of economic losses in developed nations, because metals are known to undergo corrosion when exposed to water. The existing anti-corrosion approaches, developed for protecting single-material structures, generally fail when applied to control multi-material structures. In order to meet the actual energy s...

The inhibition mechanisms of cerium salt and triethanolamine on the galvanic corrosion of AA2024-T3/graphite exposed to NaCl solution was investigated by localised electrochemical techniques. Quasi-simultaneous localized measurements of ionic current densities and pH were achieved by employing the Scanning Vibrating Electrode Technique (SVET) and t...

In this work the antifouling properties of different Plasma Electrolytic Oxidation (PEO) coatings produced on samples of 7075 aluminum alloy were studied and compared with those of samples treated with more commercial treatments, such as traditional anodizing and painting, and untreated ones. After the treatments, the different samples were charact...

The inhibitive effects provided by benzotriazole (BTA) and cerium chloride (CeCl3) on 2024-T3 aluminium alloy were assessed, individually and combined, in 0.05M NaCl electrolytes, by means of Electrochemical Impedance Spectroscopy (EIS). From the analysis of impedance fitted parameters, a synergistic effect appears to exist between both inhibitors...

Correlative characterization using atom-probe tomography (APT) and transmission electron microscopy (TEM) was performed on a tribofilm formed during sliding frictional testing with a fully formulated engine oil, which also contains a boron-based additive. The tribofilm formed is ~15. nm thick and consists of oxides of iron and compounds of B, Ca, P...

The Scanning Electrode Vibrating Technique (SVET) has been of great value for the local investigation of galvanic couplings, due to its ability to spatially separate anodic and cathodic reactions taking place on a corroding surface. However, in order to perform tests with proper sensitivity, a calibration step is carried out, usually, employing a P...

Leonardo BERTOLUCCI COELHO Mécanique des Matériaux et des Structures 2013 Revêtements hybrides déposés par voie sol-gel sur l'acier inoxydable 15-5PH en vue d'applications pour l'aéronautique : caractérisations tribologiques et en corrosion Tuteur professionnel : Pr. Florence ANSART Tuteur pédagogique : Pr. Joël DOUIN m'avoir permis la réalisation...

1) UFSC; (2) Uni-Bayreuth Coatings of a polysilazane-based ceramic/composite are a promising technology for the protection of steels for applications at higher temperatures (up to 1000ºC) and chemically harsh environments. The polymer to ceramic conversion process, from an adjusted pyrolysis treatment of the pre-ceramic polymer, allows to obtain un...