Corrosion Resistance Of Magnesium Alloy Research Articles

Corrosion resistance of a superhydrophobic polypropylene coating on magnesium alloy AZ31

Purpose To improve the corrosion resistance of magnesium alloys, the construction of protective coatings is necessary to extend the service life of Mg-based materials. Design/methodology/approach SiO2 nanoparticles modified by dodecyltrimethoxysilane (DTMS) were added to the PP and a superhydrophobic Mg(OH)2/PP-60mSiO2 composite coating was fabricated on the surface of AZ31 magnesium alloy via the hydrothermal method and subsequently the immersion treatment. Findings Hydrophilic SiO2 nanoparticles become hydrophobic after modified by DTMS, showing a higher dispersibility in xylene. By incorporating modified SiO2 nanoparticles into the composite PP coating, the hydrophobicity of the layer was enhanced, resulting in a contact angle of 166.3° and a sliding angle of 3.4°. It also improved the water repellency and durability of the coating. Furthermore, the intermediate layer of Mg(OH)2 significantly strengthened the bond between the PP layer and the substrate. The Mg(OH)2/PP-60mSiO2 composite coating significantly enhances the corrosion resistance of the magnesium alloy by effectively blocking the infiltration of the corrosion anions during corrosion. The corrosion current density of the Mg(OH)2/PP-60mSiO2 composite coating is approximately 8.23 × 10–9 A·cm-2, which can achieve a magnitude three times lower than its substrate, making it a promising surface modification for the Mg alloy. Originality/value The composite coating effectively and durably enhances the corrosion resistance of magnesium alloys.

Application and Perspectives: Magnesium Materials in Bone Regeneration.

The field of bone regeneration has always been a hot and difficult research area, and there is no perfect strategy at present. As a new type of biodegradable material, magnesium alloys have excellent mechanical properties and bone promoting ability. Compared with other inert metals, magnesium alloys have significant advantages and broad application prospects in the field of bone regeneration. By searching the official Web sites and databases of various funds, this paper summarizes the research status of magnesium composites in the field of bone regeneration and introduces the latest scientific research achievements and clinical transformations of scholars in various countries and regions, such as improving the corrosion resistance of magnesium alloys by adding coatings. Finally, this paper points out the current problems and challenges, aiming to provide ideas and help for the development of new strategies for the treatment of bone defects and fractures.

Optimization of anodizing conditions and hole sealing treatments for enhanced anti-corrosion properties of magnesium alloys

To enhance the corrosion resistance of magnesium alloys, an anti-corrosion composite film was prepared by combining anodic oxidation and sol-gel technology. Experimental results indicate that after anodization at 17.5V for 3 min, the composite film obtained through sealing with an MPTMS-modified sol exhibited significant improvements in physical properties. The thickness of the film reached 24.3 μm, its hardness was measured at 164.7 HV, and it demonstrated good surface uniformity. Electrochemical impedance spectroscopy revealed that the impedance modulus at low frequency (|Z| at 0.01 Hz) increased by nearly two orders of magnitude. Furthermore, this study thoroughly explores the corrosion protection mechanism of the composite film, highlighting the role of the sol-gel layer in occupying micro-pores and micro-cracks to form a denser and more uniform protective layer. The dual-layer protection provided by the combination of anodic oxidation and sol-gel layers significantly enhances the overall corrosion resistance of the magnesium alloy.

Comparative study of CaO and CaCO3 on microstructure refinement, mechanical and corrosion resistance of AM60 alloy

Grain refinement is a crucial technique for enhancing the mechanical properties and corrosion resistance of magnesium alloys. In this study, the addition of 0.3 wt% CaO and 0.3 wt% CaCO3 successfully refined the AM60 alloy, resulting in a significant reduction in the average grain size from 326 μm to 96 μm (when adding CaCO3). The refined grain size of the as-cast AM60 alloy led to an increase in both tensile strength and yield strength to 118.2 MPa and 72.6 MPa, representing a respective increase of 35% and 23% compared to the alloy without the refiner. As results of EBSD, it is verified that the basal slip system (0001)<112‾0> has a higher Schmid factor after adding CaO, which indicates that this system has higher activity. The substitution reaction between CaO and Mg can produce synergistic effects from the solute effect of Ca and the nucleating effect of residual CaO, which play an important role in grain refinement. Due to the fine grain size and diffuse distribution of the second phase in the AM60-CaCO3 alloy and the thermal decomposition of CaCO3, which consumes the aluminum element in the matrix, the content of the β-phase (Mg17Al12) is reduced. Consequently, this reduces the electric coupling effect between the β-phase and the magnesium matrix. The AM60-CaCO3 alloy exhibited the most superior corrosion resistance, achieving a corrosion rate of only 1.01 mm y−1, representing a 48.9% reduction in corrosion rate compared to the AM60 alloy.

Enhancing wear and corrosion resistance of magnesium alloys through in-situ Al2O3 doping for plasma electrolytic oxidation coating

The surface of PEO coatings may contain micro-cracks and pores, which can facilitate the penetration of corrosive media and initiate corrosion. Doping particles has been identified as an effective method for enhancing corrosion resistance. This study investigates the impact of in-situ doping of Al2O3 particles of varying sizes on the performance of PEO coatings. It was observed that at lower concentrations, the particles are primarily inertly doped into the coating, while larger particles tend to be deposited on the surface. The addition of Al2O3 particles through the PEO process improves breakdown and final voltages, reduces porosity, and enhances abrasion resistance of the coatings. Furthermore, the │Z│0.01 Hz of Al2O3-containing coatings remained at approximately 107 Ω⋅cm2 for 10 days during immersion in NaCl solution. The corrosion current density is reduced from 78.01 to 6.51 nA/cm2. Among the different coatings, the PEO- Al2O3-200 coating exhibited the most promising results in terms of corrosion resistance and lubricating properties. The enhanced corrosion resistance is attributed to the promotion of Mg2Al(OH)7 formation during the corrosion process.

Enhancing the corrosion resistance of magnesium alloys with biodegradable poly(trimethylene carbonate) chemical modification coating

Magnesium (Mg) alloys have great potential as biodegradable materials for medical device. However, their susceptibility to corrosion poses a significant challenge for practical applications. In this study, the poly(trimethylene carbonate)-dimethacrylate (PTMC-dMA) was employed as a coating material for ZE21B magnesium alloys. Upon UV irradiation, the PTMC-dMA macromer undergoes cross-linking to form a uniform PTMC coating with a thickness of approximately 5 μm, effectively protecting the magnesium alloy. The corrosion resistance in simulated body fluid (SBF) was evaluated through immersion testing, which showed minimal hydrogen generation (0.16 mL/cm2) during the initial 24-h period and slight corrosion observed on the PTMC-coated magnesium alloy surface after continuous immersion for 21 days. The silane coupling agent significantly enhanced the adhesive performance between the polymer and alloy. Micro-scratch tests revealed adhesion forces of 3.79 N and 5.75 N for coatings without and with the silane agent, respectively. Electrochemical tests also demonstrated the efficacy of silane treatment, showing corrosion currents of 2.100 × 108 A/cm2 for silane-treated samples compared 6.263 × 107 A/cm2 for untreated ones. Given its exceptional tensile and protective properties, this coated material is ideal for intricate bioresorbable applications, like endovascular bioresorbable stents.

Machine Learning in Enhancing Corrosion Resistance of Magnesium Alloys: A Comprehensive Review

While magnesium alloys have garnered attention for their lightweight properties across diverse applications, their susceptibility to corrosion presents a formidable challenge. Recent years have witnessed the emergence of machine learning (ML) as a formidable tool for predicting and augmenting material properties, notably corrosion resistance. This comprehensive review investigates the latest advancements and hurdles in utilizing ML techniques to investigate the corrosion behavior of magnesium alloys. This article delves into a spectrum of ML algorithms, encompassing artificial neural networks, support vector machines, and random forests, elucidating their roles in predicting corrosion rates, morphologies, and other corrosion-related characteristics in magnesium alloys. Furthermore, it underscores the pivotal challenges and opportunities within this field, such as data quality, model interpretability, and model transferability. Finally, it examines the potential of ML methods in the conception and enhancement of magnesium alloys endowed with superior corrosion resistance. This review aspires to offer valuable insights into harnessing ML’s potential for optimizing magnesium alloy designs with heightened corrosion resistance, a facet of paramount importance across diverse industries, including the automotive, aerospace, and biomedical sectors. By addressing the challenges inherent in using ML to forecast corrosion rates, including data limitations and the intricacies of corrosion mechanisms, ML stands poised to emerge as a potent instrument for advancing the development of corrosion-resistant materials.

Corrosion and wear resistant polyp-xylene composite coating on AZ31 magnesium alloy prepared by micro-arc oxidation and vapor deposition

To improve the wear and corrosion resistance of magnesium alloy, a multifunctional organic/inorganic hybrid coating was prepared on AZ31 magnesium alloy by microarc oxidation and vapor deposition of Polyp-xylene (MAO-PPX). Electrochemical tests show that the MAO-PPX composite coating can effectively block the corrosive medium and improve the corrosion resistance of magnesium alloy. Long-term corrosion protection was confirmed by neutral salt spray tests at 35 °C with 5 wt% NaCl. In addition, the MAO-PPX composite coating demonstrated a much lower friction coefficient which could be attributed to the polyp-xylene filled in the micropores of the MAO layer and transferred on the counterpart sphere. This composite coating with excellent anti-corrosion and decent lubricating properties has broad application prospects in surface protection of magnesium alloys.

Improved corrosion resistance of magnesium alloy prepared by selective laser melting through T4 heat treatment for biomedical applications

Selective laser melting (SLM) technology has broad prospects for developing magnesium alloys in structural and biomedical applications. The effects of T4 heat treatment on microstructure, mechanical properties and corrosion resistance of as-built AZ91D alloy were investigated. The results showed that after T4 treatment, β-Mg17Al12 phases distributed around the matrix changed from networks to diffuse dots and then disappeared at 420 °C for 1 h. The tensile strength and hardness of AZ91D alloy decreased after T4 treatment. In addition, electrochemical and immersion experiments showed that the corrosion resistance was greatly improved after solution. Compared with the as-built AZ91D alloy, the solution-treat sample exhibited higher corrosion resistance in Hanks' solution, and its corrosion current density was reduced by 70%, hydrogen evolution rate by 57%, and corrosion rate by about 78% in the weightless experiment. In this study, after solution-treat, the corrosion resistance of as-built AZ91D can be significantly improved while meeting the mechanical requirement of degradable alloys, and has great potential for biomedical applications.

Effect of minor Ca addition on microstructure and corrosion behavior of Mg–Y–Ca alloys

The poor corrosion resistance of magnesium and magnesium alloys limited their industry applications, especially attributed to the loose and porous corrosion product film. Moreover, it is of great importance to improve the corrosion resistance of magnesium alloy by economic and environmental protection methods. In this study, the Mg–Y–Ca alloys prepared by the addition of trace Ca and Y elements showed good corrosion resistance. In addition, the effects of minor Ca on the microstructure and corrosion behavior of Mg–1Y alloy were systematically studied. With the increase of Ca content, the corrosion resistance of Mg–1Y-xCa alloys (x = 0, 0.05, 0.1 and 0.2 wt%) was found to improve and then decrease. Among prepared Mg–1Y-xCa alloys, Mg–1Y-0.05Ca exhibited the lowest corrosion rate of 0.757 mm y−1. The high corrosion resistance of Mg–1Y-0.05Ca can be attributed to the fine grain size, and the formation of a protective corrosion passivation film rich in Y2O3, CaCO3 and (MgCa)CO3. However, the excessive addition of Ca element led to the decline of corrosion resistance, resulting from the mass generated Mg2Ca phase causing serious micro-galvanic corrosion, which destroyed the stability of the corrosion product film and damaged the corrosion protection.

Corrosion and Protection of Magnesium Alloys: Recent Advances and Future Perspectives

Magnesium alloys are of significant importance for lightweight manufacturing and weight-saving applications due to their high weight-to-strength ratio and good mechanical properties. However, the poor corrosion resistance of Mg alloys limits their large-scale practical application. An essential theoretical foundation for the development of corrosion-resistant magnesium alloys and their surface protection technologies can be elucidated via the investigation of the corrosion mechanism of the magnesium surface and the alteration of the corrosion rate after surface conversion and coating. This paper discusses some typical corrosion behaviors by originally describing the corrosion mechanism of magnesium alloys with and without different coatings and surface treatments. In order to predict the future theoretical investigation and research directions for the surface protection of magnesium alloys, some techniques and preventative measures to enhance the corrosion resistance of magnesium alloys are reviewed, and these protection techniques are intercompared for better understanding.

A super wear-resistant coating for Mg alloys achieved by plasma electrolytic oxidation and discontinuous deposition

Magnesium alloys are lightweight materials with great potential, and plasma electrolytic oxidation (PEO) is effective surface treatment for necessary improvement of corrosion resistance of magnesium alloys. However, the ∼14 µm thick and rough PEO protection layer has inferior wear resistance, which limits magnesium alloys as sliding or reciprocating parts, where magnesium alloys have special advantages by their inherent damping and denoising properties and attractive light-weighting. Here a novel super wear-resistant coating for magnesium alloys was achieved, via the discontinuous sealing (DCS) of a 1.3 µm thick polytetrafluoroethylene (PTFE) polymer layer with an initial area fraction (Af) of 70% on the necessary PEO protection layer by selective spraying, and the wear resistance was exceptionally enhanced by ∼5500 times in comparison with the base PEO coating. The initial surface roughness (Sa) under PEO+DCS (1.54 µm) was imperfectly 59% higher than that under PEO and conventional continuous sealing (CS). Interestingly, DCS was surprisingly 20 times superior for enhancing wear resistance in contrast to CS. DCS induced nano-cracks that splitted DCS layer into multilayer nano-blocks, and DCS also provided extra space for the movement of nano-blocks, which resulted in rolling friction and nano lubrication. Further, DCS promoted mixed wear of the PTFE polymer layer and the PEO coating, and the PTFE layer (HV: 6 Kg·mm−2, Af: 92.2%) and the PEO coating (HV: 310 Kg·mm−2, Af: 7.8%) served as the soft matrix and the hard point, respectively. Moreover, the dynamic decrease of Sa by 29% during wear also contributed to the super wear resistance. The strategy of depositing a low-frictional discontinuous layer on a rough and hard layer or matrix also opens a window for achieving super wear-resistant coatings in other materials.

The effect of addition of K2ZrF6 on the structures and properties of AZ31 magnesium alloy MAO coating

It is a challenge to improve the corrosion rate and blood compatibility of biomedical magnesium alloy implants in human body. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were used to study the Properties of K2ZrF6 modified AZ31 magnesium alloy composite coating. The corrosion behavior of the sample in simulated body fluid (SBF) was evaluated by hydrogen evolution corrosion, potentiodynamic polarization cur ve and electrochemical impedance spectroscopy. The results show that the corrosion resistance of magnesium alloy is significantly improved by composite coating. The wettability test shows that K2ZrF6 greatly improves the biocompatibility of MAO coating on magnesium alloy. The hemolysis test shows that the composite coating makes magnesium alloy have low hemolysis rate. The increase of PH value and magnesium ion concentration in solution caused by corrosion of magnesium alloy can be adjusted by adding K2ZrF6. The corrosion resistance mechanism of MAO coating on K2ZrF6 modified magnesium alloy was discussed. In this experiment, the optimum amount of K2ZrF6 is 4 g/L.

A new design strategy for the crack-free composite CaHPO4·2H2O/CaCO3 coating on AZ41 Mg alloy for magnesium concrete formwork

To address the limited corrosion resistance of magnesium alloys, calcium phosphorus coatings are frequently applied to their surfaces as a means of compensating for this drawback. However, cracking of traditional calcium phosphorus coatings greatly affects their protective properties. In this research, a novel CaHPO4·2H2O (DCPD) and CaCO3 composite coating with no cracks was obtained via a chemical conversion method assisted by ultrasound. DCPD coatings were also fabricated in the same method. All the coatings possess excellent adhesion strength to the substrates. In addition, electrochemical tests results show that the elimination of cracks greatly improves the anticorrosion performance of composite coatings. Optimization of the bath constituents resulted in a reduced reliance on interfacial electrochemical reactions during the co-deposition process, which plays a critical role in attaining the high-quality coating. This innovative composite coating provides a promising avenue for surface treatments of magnesium alloy concrete formwork.

Investigation of the electrochemical behavior of titanium dioxide coating on magnesium alloy

Biocompatibility and electrochemical corrosion resistance are one of the most important issues in bone implants. In the last decades, metal implants have received much attention because of their properties. Magnesium and its alloys have been widely used in orthopedics because of their biocompatibility and bone growth proprieties. Magnesium has low corrosion resistance; especially in biological environments of the body, or when exposed to blood plasma, this makes magnesium useful as an absorbable implant. To increase the corrosion resistance of magnesium alloys, and adjust the corrosion rate of the implant to the rate of bone growth, it is necessary to coat these implants. Ceramic coatings are one of the possibilities, because of their biocompatibility and high corrosion resistance. TiO2 possesses desirable properties, such as an excellent mechanical features, high corrosion resistance, and biocompatibility, which make it widely used as implant coatings material. Sol-gel is one of the effective methods for making various ceramic materials. In this study, the electrochemical properties of magnesium alloy Mg-5Gd-2.5Nd-0.5Zn-0.5Zr with and without coating with phosphate-buffered saline (PBS) are investigated through Tafel extrapolation and impedance test Titanium dioxide coating was applied to the alloys by the sol-gel method. The effect of four variables of fluoride ion content, etching time, immersion time, and the number of immersions were studied. The results of SEM images showed the optimal sample surface of a uniform coating with a thickness of 6 μm. The optimal sample corrosion current density reported 2.58 × 10−5 A/m2, which is the lowest current density in samples. The results of the impedance test also confirmed these data and the optimal sample indicated the highest value of Rp = 5003 Ω.cm2.

New Design to Provide Absolute Protection Within a Certain Period for Biodegradable Magnesium Alloys

ObjectivesMagnesium and magnesium alloy materials have excellent potential as biodegradable bone plate implants. However, the practical application of magnesium alloys is limited by their high chemical activity and poor corrosion resistance. Here, we chose a microarc fluorination (MAF) treatment to improve corrosion resistance while enhancing aspects of magnesium alloy properties. The aim of this study was to identify the effect of fixed-point corrosion on the corrosion resistance as well as the mechanical properties of magnesium alloys and to design a new corrosion-oriented model that can provide absolute protection over a period of time. Material and MethodsMAF treatment is used for surface modification of magnesium alloys to improve the corrosion resistance of magnesium alloys. To investigate the effect of the coating and indentation on the corrosion resistance of Mg alloy, electrochemical corrosion experiments were carried out. It is worth mentioning that in this experiment we measured and analyzed the mechanical properties of the samples, especially the tensile strength. ResultsIn the innovative indentation sample test, the coated specimens showed lower tensile strength due to the occurrence of fixed-point corrosion. To avoid the loss of mechanical properties due to fixed-point corrosion, we proposed a new idea (Corrosion-oriented Design). Ultimately, the immersion experiments as well as the mechanical properties analysis concluded that the Corrosion-oriented Design samples could maintain the mechanical properties without detectable loss for a long time. ConclusionThe Corrosion-oriented Design model can avoid the nuisance of fixed-point corrosion and control the centralized orientation of corrosion. This provides a new direction for the clinical application of magnesium alloys, which may offer a completely stable bone-healing condition in trauma treatment and avoid the drawbacks caused by the previous uncontrolled corrosion.

Effect of Surface Strain to Hydroxide Layer Formation on High-Pressure Die Casting Magnesium Alloy

Magnesium hydroxide layer improve corrosion resistance of magnesium alloys. Nonuniform strain on magnesium alloys surface was reported that affected to layer formation and corrosion resistance properties. Hydroxide layer formed to high pressure die cast ASTM AZ91D magnesium alloy, then investigated to correlation between hydroxide layer formation and residual stress and strain distribution on alloy surface which were measured by X-ray. Strain distribution was evaluated by full width half maximum (FWHM) value. Formed hydroxide layer was well compatible with FWHM distribution in as cast specimen. Heat treated for homogenization was carried out to inspection for correlation FWHM. FWHM was significantly lowering by heat treatment. Hydroxide layer tends to thin where FWHM value was low, therefore correlation between nonuniform strain and hydroxide layer formation was found out.

In situ Micro‐Arc Oxidation‐Induced Growth of Black Ceramic ZrO2 and CuO Coatings on Magnesium Alloys and their Electrochemical Analysis

AbstractIn this paper, a new environmentally friendly micro‐arc oxidation (MAO) colorant coating was proposed, which greatly improved the corrosion resistance of magnesium alloy. Herein, the black MAO coatings with uniform color and superior performance were successfully prepared on AZ91D alloy to expand the application of magnesium alloy. It was found that the color of the MAO coatings changes from white (80.76) to black (19.92) with the increased concentration of cupric pyrophosphate, attributed to the formation of copper compounds (CuO) in the outer layer of MAO coatings. In addition, electrochemical corrosion tests were also carried out in 3.5 wt% NaCl solution. And it was found that the corrosion potential and current were −1.32 V and 1.06×10−6 A/cm2, respectively, which increased by 0.15 V and decreased by 3.16×10−6 A/cm2 compared to those without cupric pyrophosphate. In conclusion, black MAO coatings produced at a cupric pyrophosphate concentration of 6 g/L, an oxidation time of 17 min, and a termination voltage of 375 V had an excellent performance and superior corrosion resistance. Therefore, it was provided a new idea for the research of surface in‐situ treatment technology with the composite of zirconia salt electrolyte and cupric pyrophosphate.

Advances in the Modification of Silane-Based Sol-Gel Coating to Improve the Corrosion Resistance of Magnesium Alloys

As the lightest structural materials, magnesium (Mg) alloys play a significant role in vehicle weight reduction, aerospace, military equipment, energy saving, and emission reduction. However, the poor corrosion resistance of Mg alloys has become a bottleneck restricting its wide application. Developing a good surface protective coating can effectively improve the corrosion resistance of Mg alloys. The silane-based sol-gel coating technology has been widely used in the corrosion protection of Mg alloys in recent years due to its advantages of simple process, accessible tailoring of film composition and structure, and excellent corrosion resistance. Whereas the synthesis of sol-gel coatings includes the hydrolysis and dehydration process, which may inherently contain micron or nano defects in the coatings, thereby making it detrimental to the anti-corrosion effect. Therefore, in order to enhance their protection against corrosion, the appropriate modification of sol-gel coatings has become a current research hotspot. This review is based on the modification methods of silane-based sol-gels on the surface of Mg alloys, which are divided into four categories: bare sol-gel, nanoparticles, corrosion inhibitors, and sol-gel-based composite coatings. The modification methods and corrosion protection mechanism are discussed respectively, and the application, development, and research strategies of silane-based sol-gel coatings are included.

Investigations of microstructure and corrosion resistance of WC-Co and WC-Cr3C2-Ni coatings deposited by HVOF on magnesium alloy substrates

Magnesium alloys have found widespread application in various industries, mainly due to the combination of low density, the best structural material known today, and high strength to weight ratio. However, the use of magnesium alloys is limited due to their poor wear and corrosion behavior. In this study, two commercial powders, agglomerated and sintered WC-Co and WC-Cr3C2-Ni were thermally sprayed to deposit coatings onto two magnesium alloy substrates (AZ31 and AZ91) with a combination of two different spraying distances (320 and 400 mm). The main aim of this work was to investigate the microstructure and corrosion resistance of the coatings deposited by High Velocity Oxy Fuel (HVOF) spraying. The morphology and microstructure of the sprayed coatings were analyzed by Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Additionally, porosity, microhardness and surface roughness were examined. Furthermore, potentiodynamic polarization was used to characterize the corrosion behavior of the deposited coatings. The experimental results showed that manufactured coatings are characterized by a dense microstructure with porosity typical for coatings sprayed with the HVOF method. Moreover small cracks and unmelted carbide particles embedded in the metal matrix were found in the as-sprayed coatings. Based on the results of the potentiodynamic studies it was found that the corrosion resistance of AZ31 and AZ91 magnesium alloys is not very high in a sodium chloride solution. The polarization resistance of AZ31 is very low (241.3 Ω∙cm2) and the corrosion current density is high (57.4 μA∙cm−2), whereas for AZ91 these values are 17.8 Ω∙cm2 and 1612.1 μA∙cm−2, respectively. The corrosion potential of the AZ31 and AZ91 alloy equal −1.56 V which is characteristic for magnesium alloys in a NaCl solution. For both type of substrates, better corrosion resistance has been obtained for the WC-Co coating. The Rp value was nearly 150 times higher than the one for uncoated AZ91 alloy, whereas for AZ31 the polarization resistance was about 17 times higher (Rp = 4.2 kΩ∙cm2) in comparison to non-covered alloy. In summary, all deposited coatings improved the corrosion resistance of the magnesium alloy. However, the WC-Co one protects the magnesium substrate against corrosion more effectively than the WC-Cr3C2-Ni.