Corrosion behavior of friction stir welded AZ31B magnesium alloy with plasma electrolytic oxidation coating formed in silicate electrolyte

Alcohol used as an additive could act not only as a leveler for the formation of compact film but also as an enhancer for film qualities, such as corrosion resistance and withstand voltage.

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Improving the wear properties of AZ31 magnesium alloy under vacuum low-temperature condition by plasma electrolytic oxidation coating

Acta Astronautica ◽

10.1016/j.actaastro.2015.07.005 ◽

2015 ◽

Vol 116 ◽

pp. 126-131 ◽

Cited By ~ 10

Author(s):

Hang Li ◽

Songtao Lu ◽

Wei Qin ◽

Lu Han ◽

Xiaohong Wu

Keyword(s):

Magnesium Alloy ◽

Low Temperature ◽

Plasma Electrolytic Oxidation ◽

Az31 Magnesium Alloy ◽

Wear Properties ◽

Plasma Electrolytic Oxidation Coating ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

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Influence of Plasma Electrolytic Oxidation coating on corrosion characteristics of Friction Stir Welded ZE41 rare earth Magnesium alloy

Surface Topography Metrology and Properties ◽

10.1088/2051-672x/ac4343 ◽

2021 ◽

Author(s):

N Sivashanmugam ◽

KL Harikrishna ◽

S R Koteswara Rao ◽

N Rameshbabu ◽

P Manojkumar

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Rare Earth ◽

Magnesium Alloy ◽

Plasma Electrolytic Oxidation ◽

Dense Layer ◽

Metallographic Examination ◽

Friction Stir ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

Abstract Magnesium and its alloys are extensively used in the defence, aerospace and automotive industries, owing to their excellent mechanical properties. But there is a requirement of corrosion prevention treatment before using it for applications, since the corrosion resistance of Mg alloy is poor. In this work, a study on the mechanical properties of friction stir welded ZE41 rare earth magnesium alloy thick plates of 15mm and 25mm, was carried out. A metallographic examination and mechanical tests were conducted on both the welds. Furthermore, Plasma Electrolytic Oxidation (PEO), a surface conversion treatment was carried out on both the base material as well as on the friction stir butt joints. X-ray diffraction and scanning electron microscopy analysis were carried out on all the samples, with and without coating. The coated and uncoated samples were assessed by potentiodynamic polarisation (PDP) tests and electrochemical impedance spectroscopy (EIS) to study the electrochemical corrosion behaviour. An outer porous layer and an inner dense layer, have been identified from the SEM images. From the corrosion tests results it was revealed that there was an improvement in the corrosion resistance of both the base metal as well as the weldments by the PEO coating process.

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Comparison of Electrochemical and Chemical Corrosion Behavior of MRI 230D Magnesium Alloy with and without Plasma Electrolytic Oxidation Treatment

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.364.27 ◽

2015 ◽

Vol 364 ◽

pp. 27-34

Author(s):

Barbara Kazanski ◽

Alex Lugovskoy ◽

Ohad Gaon ◽

Michael Zinigrad

Keyword(s):

Magnesium Alloy ◽

Magnesium Alloys ◽

Corrosion Behavior ◽

Plasma Electrolytic Oxidation ◽

Electrochemical Impedance ◽

Weight Ratio ◽

Open Circuit ◽

Chemical Corrosion ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

Magnesium is one of the lightest metals and magnesium alloys have quite special properties, interest to which is continuously growing. In particular, their high strength-to-weight ratio makes magnesium alloys attractive for various applications, such as transportation, aerospace industryetc. However, magnesium alloys are still not as popular as aluminum alloys, and a major issue is their corrosion behavior.The present research investigated the influence of the PEO treatment on the corrosion behavior of MRI 230M magnesium alloy. Plasma electrolytic oxidation (PEO) of an MRI 230M alloy was accomplished in a silicate-base electrolyte with KF addition using an AC power source.The corrosion behavior of both treated and untreated samples was evaluated by open circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS), linear polarization tests, linear sweep voltammetry (Tafel extrapolation) and chemical methods, such as mass loss and hydrogen evolution, in neutral 3.0 wt% NaCl solution.According to the tests results, PEO process can affect the corrosion resistance of MRI 230M magnesium alloy, though its action is not always unambiguous. An attempt to explain the influence of the PEO treatment on the corrosion behavior of the alloy is presented.

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