Introduction to Plasma Electrolytic Oxidation—An Overview of the Process and Applications

Plasma electrolytic oxidation (PEO), also called micro-arc oxidation (MAO), is an innovative method in producing oxide-ceramic coatings on metals, such as aluminum, titanium, magnesium, zirconium, etc. The process is characterized by discharges, which develop in a strong electric field, in a system consisting of the substrate, the oxide layer, a gas envelope, and the electrolyte. The electric breakdown in this system establishes a plasma state, in which, under anodic polarization, the substrate material is locally converted to a compound consisting of the substrate material itself (including alloying elements) and oxygen in addition to the electrolyte components. The review presents the process kinetics according to the existing models of the discharge phenomena, as well as the influence of the process parameters on the process, and thus, on the resulting coating properties, e.g., morphology and composition.

Download Full-text

Oxide ceramic coatings on aluminium alloys produced by a pulsed bipolar plasma electrolytic oxidation process

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2004.10.147 ◽

2005 ◽

Vol 199 (2-3) ◽

pp. 150-157 ◽

Cited By ~ 198

Author(s):

A.L. Yerokhin ◽

A. Shatrov ◽

V. Samsonov ◽

P. Shashkov ◽

A. Pilkington ◽

...

Keyword(s):

Aluminium Alloys ◽

Plasma Electrolytic Oxidation ◽

Oxidation Process ◽

Ceramic Coatings ◽

Oxide Ceramic ◽

Electrolytic Oxidation ◽

Oxide Ceramic Coatings ◽

Plasma Electrolytic

Download Full-text

Simultaneous Reduction of Wear and Corrosion of Titanium, Magnesium and Zirconium Alloys by Surface Plasma Electrolytic Oxidation Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.38.27 ◽

2008 ◽

Vol 38 ◽

pp. 27-35 ◽

Cited By ~ 9

Author(s):

H.M. Nykyforchyn ◽

V.S. Agarwala ◽

M.D. Klapkiv ◽

V.M. Posuvailo

Keyword(s):

Corrosion Resistance ◽

Plasma Electrolytic Oxidation ◽

Synthesis Method ◽

Zirconium Alloys ◽

Ceramic Coatings ◽

Oxide Ceramic ◽

Wear And Corrosion ◽

Electrolytic Oxidation ◽

Wear And Corrosion Resistance ◽

Plasma Electrolytic

Titanium, magnesium and zirconium alloys are widely used in industrial applications, which require high wear and corrosion resistance. However current methods of improving these properties often do not satisfy the requirements of service and functional properties. An alternative approach is the application of oxide-ceramic coatings using high temperature process. The coatings are applied by spark discharge plasma in the metal-electrolyte system at high voltages - PEO (plasma electrolytic oxidation) as an oxide synthesis method. This method has shown good results for aluminium alloys and with good prospects to be used for titanium, magnesium and zirconium alloys. Development of PEO technology to improve the wear and corrosion resistance of titanium, magnesium and zirconium alloys is discussed in this paper. It describes the methods for obtaining the required layer-thickness for a specified hardness, porosity, wear and corrosion resistance, sets up the optimal process parameters (voltage/current) by taking the relation of anodic to cathodic currents into account, and establishing the electrolyte content of different dopants.

Download Full-text

Plasma electrolytic oxidation technology for producing protective coatings of aluminum alloys

Kompleksnoe ispolʹzovanie mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik shikisattardy Keshendi Paidalanu ◽

10.31643/2021/6445.21 ◽

2021 ◽

Vol 317 (2) ◽

pp. 78-93

Author(s):

G.B. Yeshmanova ◽

◽

D.U. Smagulov ◽

C. Blawert ◽

◽

...

Keyword(s):

Aluminum Alloys ◽

Plasma Electrolytic Oxidation ◽

High Performance ◽

Protective Coatings ◽

Chemical Properties ◽

High Hardness ◽

Ceramic Coatings ◽

Oxide Ceramic ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

Today, the technology of hardening the surface layers of parts and the creation of protective coatings on the surface with high physical, mechanical and chemical properties is particularly effective. The article reviews the most promising innovative technologies for surface hardening of aluminum alloys – plasma electrolytic oxidation (PEO). Possible conditions and mechanisms for the formation of protective coatings on the surface of aluminum alloys are considered. The influence of the main parameters of PEO processing (electrical parameters, composition and concentration of electrolyte, the influence of alloying elements) on the structure and properties of oxide-ceramic coatings has been studied. The qualitative characteristics of the surface layer of samples and finished products made of aluminum alloys have shown the effectiveness of the PEO technology, which makes it possible to obtain ceramic coatings with high hardness, strength, increased wear and corrosion resistance. Possible areas of application of high-performance technologies for the deposition of protective PEO coatings on the surface of products made of aluminum alloys are proposed.

Download Full-text

Effect of Sodium Silicate Concentration on Morphology of Ceramic Coatings Produced on Commercially Pure Aluminum Using Plasma Electrolytic Oxidation

Russian Journal of Non-Ferrous Metals ◽

10.3103/s1067821220060097 ◽

2020 ◽

Vol 61 (6) ◽

pp. 762-767

Author(s):

M. Khorasanian ◽

F. Shamsi ◽

S. M. Lari Baghal

Keyword(s):

Sodium Silicate ◽

Plasma Electrolytic Oxidation ◽

Pure Aluminum ◽

Ceramic Coatings ◽

Silicate Concentration ◽

Commercially Pure ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

Download Full-text

SEM and EDS Characterization of Porous Coatings Obtained On Titaniumby Plasma Electrolytic Oxidation in Electrolyte Containing Concentrated Phosphoric Acid with Zinc Nitrate

Advances in Materials Science ◽

10.1515/adms-2017-0010 ◽

2017 ◽

Vol 17 (2) ◽

pp. 41-54 ◽

Cited By ~ 6

Author(s):

K. Rokosz ◽

T. Hryniewicz ◽

K. Pietrzak ◽

W. Malorny

Keyword(s):

Phosphoric Acid ◽

Plasma Electrolytic Oxidation ◽

Pure Titanium ◽

Zinc Nitrate ◽

Porous Coatings ◽

Electrolytic Oxidation ◽

Micro Arc Oxidation ◽

Plasma Electrolytic ◽

Peo Coatings

AbstractThe SEM and EDS results of porous coatings formed on pure titanium by Plasma Electrolytic Oxidation (Micro Arc Oxidation) under DC regime of voltage in the electrolytes containing of 500 g zinc nitrate Zn(NO3)2·6H2O in 1000 mL of concentrated phosphoric acid H3PO4at three voltages, i.e. 450 V, 550 V, 650 V for 3 minutes, are presented. The PEO coatings with pores, which have different shapes and the diameters, consist mainly of phosphorus, titanium and zinc. The maximum of zinc-to-phosphorus (Zn/P) ratio was found for treatment at 650 V and it equals 0.43 (wt%) | 0.20 (at%), while the minimum of that coefficient was recorded for the voltage of 450 V and equaling 0.26 (wt%) | 0.12 (at%). Performed studies have shown a possible way to form the porous coatings enriched with zinc by Plasma Electrolytic Oxidation in electrolyte containing concentrated phosphoric acid H3PO4with zinc nitrate Zn(NO3)2·6H2O.

Download Full-text