@cenim.csic.es
Departamento de Ingeniería de Superficies, Corrosión y Durabilidad/CENIM CSIC
CENIM-CSIC
Dr. Feliu Jr. graduated with Honors in the specialty of Metallurgy at the Faculty of Chemistry of the Complutense University of Madrid in 1987. He took a particular interest in the field of corrosion, largely due to interesting and fruitful conversations with Prof. S. Feliu, my father. In 1988, he was awarded with a Ph.D. scholarship funded by the Spanish National Research Council (CSIC). In 1990, he completed his Doctoral Thesis under the direction of Professors Manuel Morcillo and Jose Maria Bastidas in the Department of Corrosion at CENIM. His PhD was primarily focus on the use of impedance measurements to obtain information about the effect of replacement of part of the zinc by Fe2P extender on the anti-corrosive properties of zinc-rich coatings. Following his PhD, Feliu Jr joined the group of Prof. James Castle at the Surrey University, England, in 1991, as an Honorary Research Fellow, where he used X-ray photoelectron spectroscopy (XPS) to examine ...(
PhD in Chemistry U. Complutense (Madrid) 1990
Degree in Chemistry U. Complutense (Madrid) 1990
Metals and Alloys, Surfaces, Coatings and Films, Materials Chemistry, Materials Science
https://www.mdpi.com/2075-4701/10/6/775
https://www.researchgate.net/publication/333774252_Composition_Structure_and_Protective_Properties_Of_Air-Formed_Oxide_Films_On_Magnesium_Alloys
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Sebastian Feliu, Lucien Veleva, and Federico García-Galvan
MDPI AG
In this work, the corrosion behaviors of the AZ31B alloy in Ringer’s solution at 20 °C and 37 °C were compared over four days to better understand the influence of temperature and immersion time on corrosion rate. The corrosion products on the surfaces of the AZ31B alloys were examined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Electrochemical impedance spectroscopy (EIS) provided information about the protective properties of the corrosion layers. A significant acceleration in corrosion rate with increasing temperature was measured using mass loss and evolved hydrogen methods. This temperature effect was directly related to the changes in chemical composition and thickness of the Al-rich corrosion layer formed on the surface of the AZ31B alloy. At 20 °C, the presence of a thick (micrometer scale) Al-rich corrosion layer on the surface reduced the corrosion rate in Ringer’s solution over time. At 37 °C, the incorporation of additional Mg and Al compounds containing Cl into the Al-rich corrosion layer was observed in the early stages of exposure to Ringer’s solution. At 37 °C, a significant decrease in the thickness of this corrosion layer was noted after four days.
Lucien Veleva, Mareny Guadalupe Fernández-Olaya, and Sebastián Feliu
MDPI AG
The initial stages of corrosion of AZ31B magnesium alloy, immersed in Ringer′s solution at 37 °C body temperature for four days, have been evaluated by independent gravimetric and chemical methods and through electrochemical impedance spectroscopy (EIS) measurements. The corrosion current densities estimated by hydrogen evolution are in good agreement with the time-integrated reciprocal charge transfer resistance values estimated by EIS. The change in the inductive behavior has been correlated with difference in the chemical composition of corrosion layers. At the shorter immersion of 2 days, EDS analysis of cross section of the uniform corrosion layer detected Cl and Al elements, perhaps as formed aluminum oxychlorides salts.
M.C. Delgado, F.R. García-Galvan, I. Llorente, P. Pérez, P. Adeva, and S. Feliu
Elsevier BV
S. Feliu, F. R. García‐Galvan, I. Llorente, L. Diaz, and J. Simancas
Wiley
The influence of the presence of hydrogen bubbles adhered to the corroding specimen surface on the EIS estimations of corrosion rate of magnesium alloys is considered. The EIS corrosion rates for AZ31 specimens exposing a small area were four times higher than the real values determined by gravimetric or hydrogen evolution measurements. In contrast, no significant differences in the corrosion rate have been observed in the case of the AZ61 specimens. A progressive deterioration in the protective properties of the corrosion products layer formed during the test was observed only on AZ31 specimens exposing a small area.
S. Feliu and I. Llorente
Elsevier BV
L. Diaz, F. R. García-Galván, I. Llorente, A. Jiménez-Morales, J. C. Galván, and S. Feliu Jr
Royal Society of Chemistry (RSC)
The influence of heat treatment of magnesium alloy substrates on corrosion resistance of a sol–gel coating has been assessed during immersion tests in 0.6 M NaCl aqueous solution.
Sebastián Feliu, Alejandro Samaniego, Violeta Barranco, A.A. El-Hadad, Irene Llorente, Carmen Serra, and J.C. Galván
Elsevier BV
A. Samaniego, K. Gusieva, I. Llorente, S. Feliu, and N. Birbilis
Elsevier BV
A.A. El-Hadad, V. Barranco, A. Samaniego, I. Llorente, F.R. García-Galván, A. Jiménez-Morales, J.C. Galván, and S. Feliu
Elsevier BV
Sebastián Feliu, Jr., Alejandro Samaniego, Elkin Bermudez, Amir El-Hadad, Irene Llorente, and Juan Galván
MDPI AG
Possible relations between the native oxide film formed spontaneously on the AZ31 and AZ61 magnesium alloy substrates with different surface finish, the chemistry of the outer surface of the conversion coatings that grows after their subsequent immersion on saturated aqueous NaHCO3 solution treatment and the enhancement of corrosion resistance have been studied. The significant increase in the amount of aluminum and carbonate compounds on the surface of the conversion coating formed on the AZ61 substrate in polished condition seems to improve the corrosion resistance in low chloride ion concentration solutions. In contrast, the conversion coatings formed on the AZ31 substrates in polished condition has little effect on their protective properties compared to the respective as-received surface.
Sebastián Feliu, Alejandro Samaniego, Violeta Barranco, A.A. El-Hadad, Irene Llorente, and P. Adeva
Elsevier BV
Alejandro Samaniego, Irene Llorente, and Sebastián Feliu
Elsevier BV
Sebastián Feliu, Alejandro Samaniego, A.A. El-Hadad, and Irene Llorente
Elsevier BV
A. Pardo, S. Feliu, M. C. Merino, M. Mohedano, P. Casajús, and R. Arrabal
Informa UK Limited
The corrosion protection of Mg–Al alloys by flame thermal spraying of Al/SiC particles (SiCp) composite coatings was evaluated by electrochemical impedance spectroscopy in 3.5 wt.% NaCl solution. The volume fraction of SiCp varied between 5 and 30%. The as-sprayed Al/SiCp composite coatings revealed a high number of microchannels, largely in the vicinity of the SiCp, that facilitated the penetration of the electrolyte and the subsequent galvanic corrosion of the magnesium substrates. The application of a cold-pressing post-treatment reduced the degree of porosity of the coatings and improved the bonding at the coating/substrate and Al/SiC interfaces. This resulted in improved corrosion resistance of the coated specimens. The effectiveness of the coatings slightly decreased with the addition of 5–30 vol.% SiCp compared with the unreinforced thermal spray aluminium coatings.
Sebastián Feliu, C. Maffiotte, A. Samaniego, Juan Carlos Galván, and Violeta Barranco
Elsevier BV
Sebastián Feliu, C. Maffiotte, Juan Carlos Galván, and Violeta Barranco
Elsevier BV
Sebastián Feliu, C. Maffiotte, Alejandro Samaniego, Juan Carlos Galván, and Violeta Barranco
Elsevier BV
A. Pardo, M.C. Merino, R. Arrabal, P. Casajús, M. Mohedano, S. Feliú, and S. Merino
Association for Materials Protection and Performance (AMPP)
Abstract The corrosion behavior of AZ31, AZ80, and AZ91D Mg-Al-Zn alloys coated with aluminum and Al-11Si thermal spray was evaluated in 3.5 wt% sodium chloride (NaCl) solution at 22°C by gravimetric and electrochemical impedance spectroscopy (EIS) measurements. The corrosion products were examined using scanning electron microscopy (SEM), energy-dispersive x-ray analysis (EDX), and low-angle x-ray diffraction (XRD). The as-sprayed aluminum and Al-11Si coatings were porous, and galvanic corrosion of magnesium substrates was observed at the substrate/coating interfaces. Application of a cold-pressing posttreatment smoothed and densified the coatings, improved the contact between coating and substrate, and substantially increased the corrosion resistance. Cold-pressed aluminum coatings were an effective barrier against corrosion and revealed the same corrosion performance, regardless of the composition of the magnesium substrate. However, cold-pressed Al-11Si coatings were permeable to the chloride-containi...
A. Pardo, S. Feliu, M. C. Merino, R. Arrabal, and E. Matykina
Hindawi Limited
The corrosion rate of AZ31, AZ80, and AZ91D magnesium/aluminium alloys immersed in 3.5 wt.% NaCl was determined comparing gravimetric and electrochemical measurements. The findings revealed that, for all investigated materials, a fraction of the metallic surface exposed to the corrosive medium did not reveal a normal electrochemical response to the applied signal. This may be associated with phenomena such as partial disintegration of specimens into fine metallic particles, electrochemical formation of ions, and/or anomalous chemical attack occurring simultaneously with the normal electrochemical corrosion attack. The abnormal electrochemical behaviour was more evident for lower amounts of aluminium in the bulk composition of the investigated materials. Thus, the electrochemical estimates of pure Mg and the AZ31 alloy were not reliable and tended to underestimate corrosion losses.
A. Pardo, S. Feliu Jr, M. C. Merino, M. Mohedano, P. Casajús, and R. Arrabal
Editorial CSIC
The corrosion protection of Mg-Al alloys by flame thermal spraying of Al/SiCp composite coatings was evaluated by electrochemical impedance spectroscopy in 3.5 wt.% NaCl solution. The volume fraction of SiC particles (SiCp) varied between 5 and 30%. The as-sprayed Al/SiCp composite coatings revealed a high number of micro-channels, largely in the vicinity of the SiC particles, that facilitated the penetration of the electrolyte and the subsequent galvanic corrosion of the magnesium substrates. The application of a cold-pressing post-treatment reduced the degree of porosity of the coatings and improved the bonding at the coating/substrate and Al/SiC interfaces. This resulted in improved corrosion resistance of the coated specimens. The effectiveness of the coatings slightly decreased with the addition of 5-30 vol.% SiCp compared with the unreinforced thermal spray aluminium coatings.
S. Feliu, A. Pardo, M.C. Merino, A.E. Coy, F. Viejo, and R. Arrabal
Elsevier BV
A. Pardo, S. Feliú, M. C. Merino, R. Arrabal, and E. Matykina
Hindawi Limited
The chemical changes that take place on the rare earth treated surface of the A361 aluminium alloy exposed to air at temperatures between 100 and500∘Chave been examined using X-ray photoelectron spectroscopy (XPS). The most notable features discussed in this work are the disappearance of Mg and Si signals at the tested temperatures and disappearance of the Ce signal at temperatures of 400–500∘C. The biphasic microstructure of the A361 alloy, constituted by close to 12 wt% Si and the Al matrix, plays an important role in many of the results obtained. The notable growth of aluminium oxide across the conversion coating in the case of the Ce-treated surface is related to the structural transformation experienced by the cerium oxide coating at 400–500∘C.
Winner of the Metals 2022 Best Paper Award (