Next Article in Journal
Influences of TiAlN Coating on Cutting Temperature during Orthogonal Machining H13 Hardened Steel
Next Article in Special Issue
Degradation Behaviour of Mg0.6Ca and Mg0.6Ca2Ag Alloys with Bioactive Plasma Electrolytic Oxidation Coatings
Previous Article in Journal
Effects of Selective Laser Modification and Al Deposition on the Hot Corrosion Resistance of Ceria and Yttria-Stabilized Zirconia Thermal Barrier Coatings
Previous Article in Special Issue
Characterization, Bioactivity and Antibacterial Properties of Copper-Based TiO2 Bioceramic Coatings Fabricated on Titanium
Open AccessFeature PaperArticle

LDH Post-Treatment of Flash PEO Coatings

1
Departamento de Ciencia de Materiales, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain
2
School of Materials, University of Manchester, Oxford Road, Manchester M13 9PL, UK
*
Author to whom correspondence should be addressed.
Coatings 2019, 9(6), 354; https://doi.org/10.3390/coatings9060354
Received: 25 April 2019 / Revised: 23 May 2019 / Accepted: 28 May 2019 / Published: 30 May 2019
(This article belongs to the Special Issue Plasma Electrolytic Oxidation (PEO) Coatings)
This work investigates environmentally friendly alternatives to toxic and carcinogenic Cr (VI)-based surface treatments for aluminium alloys. It is focused on multifunctional thin or flash plasma electrolytic oxidation (PEO)-layered double hydroxides (LDH) coatings. Three PEO coatings developed under a current-controlled mode based on aluminate, silicate and phosphate were selected from 31 processes (with different combinations of electrolytes, electrical conditions and time) according to corrosive behavior and energy consumption. In situ Zn-Al LDH was optimized in terms of chemical composition and exposure time on the bulk material, then applied to the selected PEO coatings. The structure, morphology and composition of PEO coatings with and without Zn-Al-LDH were characterized using XRD, SEM and EDS. Thicker and more porous PEO coatings revealed higher amounts of LDH flakes on their surfaces. The corrosive behavior of the coatings was studied by electrochemical impedance spectroscopy (EIS). The corrosion resistance was enhanced considerably after the PEO coatings formation in comparison with bulk material. Corrosion resistance was not affected after the LDH treatment, which can be considered as a first step in achieving active protection systems by posterior incorporation of green corrosion inhibitors. View Full-Text
Keywords: PEO; LDH; active protection; corrosion; aluminium PEO; LDH; active protection; corrosion; aluminium
Show Figures

Graphical abstract

MDPI and ACS Style

del Olmo, R.; Mohedano, M.; Mingo, B.; Arrabal, R.; Matykina, E. LDH Post-Treatment of Flash PEO Coatings. Coatings 2019, 9, 354.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop