Corrosion Resistance Of Magnesium Research Articles

Influence of the activation time of magnesium surfaces on the concentration of active hydroxyl groups and corrosion resistance

Magnesium alloys have been extensively studied as degradable biomaterials for clinical applications due to their biocompatibility and mechanical properties. However, their poor corrosion resistance can lead to issues such as osteolysis and the release of gaseous hydrogen. This study investigated the influence of the activation time of magnesium surfaces in a sodium hydroxide (NaOH) solution on the concentration of active hydroxyl groups and corrosion resistance. The results indicated that immersion time significantly influences the formation of a corrosion-resistant film and the distribution of surface hydroxyl groups. Specifically, specimens treated for 7.5 h exhibited the highest concentration of hydroxyl groups and the most uniform oxide film distribution. Electrochemical tests demonstrated capacitive behavior and passive surface formation for all evaluated times, with the 7.5-h immersion in NaOH yielding superior corrosion resistance, lower current density, and a more efficient and thicker protective film. SEM and EDS analyses confirmed increased formation of Mg(OH)₂ for samples treated for 5 and 7.5 h, while a 10-h treatment resulted in a brittle, porous layer prone to degradation. Statistical analysis using ANOVA and Fisher's LSD test corroborated these findings. The optimal 7.5-h alkali treatment enhanced magnesium's corrosion resistance and surface properties, making it a promising candidate for orthopedic implants. However, further studies are necessary to assess biocompatibility and physiological responses before clinical implementation.

Simultaneously improving mechanical and anti-corrosion properties of extruded Mg-Al dilute alloy via trace Er addition

Simultaneously improving the mechanical properties and corrosion resistance of magnesium (Mg) alloys is a long-standing challenge to be solved in their engineering applications. In this work, we find that trace Er addition can improve the mechanical and anti-corrosion properties of Mg-1.4Al-0.4Mn-0.4Ca-0.3Er (wt%, AMXE) dilute alloy synergistically, especially reducing the corrosion rate (0.75 mm y–1) by one order of magnitude compared with the reference Mg-1.4Al-0.4Mn-0.4Ca (AMX) alloy and making it comparable to that of high-purity Mg. Adding trace Er reduces the dynamic recrystallization degree and increases the strengthening phase particles, which is mainly responsible for the increase of yield strength by 42 MPa. The addition of Er promotes the formation of much less noble Al8Mn4Er with effective Fe trapping ability and induces dislocation segregation, thus dramatically reducing micro-galvanic corrosion tendency. Meanwhile, Er addition promotes the formation of a more passivation and dense corrosion film. These two factors together lead to the extremely low corrosion rate of AMXE alloy. Our findings are expected to promote the development of low alloyed high performance Mg alloys.

Improving magnesium's corrosion resistance through tannic acid–polyethyleneimine coatings for bioresorbable implant applications

A TA–PEI coating on magnesium successfully achieved a tolerable corrosion rate for biodegradable implant applications.

Advances in coatings on Mg alloys and their anti-microbial activity for implant applications

Magnesium matrix composites reinforced by calcium phosphate could not show the desired effect on the magnesium breakdown rate. Rapid disintegration rate limited the magnesium alloys used as biodegradable implant material. The rate of degradation can be minimized and biological activity can be improved in the magnesium alloy by Hydroxyapatite (HA) coating with the improvement of bone induction and conduction abilities. Various alkali post-treatment and conversion coating methods are applied to deposit HA coatings and biocompatible dicalcium phosphate dihydrate (DCPD) on magnesium alloy so that corrosion resistance and surface biocompatibility can be improved to be used in bone tissue engineering applications. Magnesium's corrosion resistance will weaken its antibacterial properties, which are linked to and proportional to the alkaline pH at the time of breakdown. The goal of this study is to bring together and compare contemporary research on different coatings on magnesium and related alloys in relation to antibacterial functionalized activities. A though review has been performed on in vivo and in vitro cytocompatibility, material property, corrosion resistance, and antibacterial properties of the coatings. Increased degradation behavior, biocompatibility, and bioactivity have been achieved following multiple procedures such as alkali treatment with HA electrochemical deposition on magnesium alloy. Multifunctional coatings can make safe and bioactive magnesium alloy surfaces for biodegradable implant applications.

Corrosion properties and biocompatibility of strontium doped calcium phosphate coated magnesium prepared by electrodeposition

The initial corrosion resistance and bioactivity of biodegradable magnesium is a major success factor in implant applications. In this study, Calcium phosphate doped Strontium was coated on magnesium by electrodeposition. The surface characteristics and biocompatibility of Calcium phosphate coated magnesium according to the Sr content were evaluated. The strontium-calcium phosphate coating was uniformly coated on the magnesium surface and strontium-calcium phosphate coating layer prevents damage and local corrosion of the magnesium surface. In addition, as the strontium content increased, the corrosion resistance of magnesium was improved. Cytotoxicity was evaluated through an in vitro test using the osteoblasts. Cell proliferation improved with increasing strontium content. Modified magnesium was implantation in rat tibia for 4 weeks and the effect on bone regeneration was confirmed. As a result, bone regeneration of strontium-calcium phosphate coated magnesium was improved. strontium-calcium phosphate coating on magnesium showed improved corrosion resistance, biocompatibility and improved bone regeneration, which may be beneficial for clinical use.

Fluoride Coatings on Magnesium Alloy Implants.

After several years of research and development, it has been reported that magnesium alloys can be used as degradable metals in some medical device applications. Over the years, fluoride coatings have received increasing research attention for improving the corrosion resistance of magnesium. In this paper, different methods for preparing fluoride coatings and the characteristics of these coatings are reported for the first time. The influence of the preparation conditions of fluoride coatings, including the magnesium substrate, voltage, and electrolyte, on the coatings is discussed. Various properties of magnesium fluoride coatings are also summarized, with an emphasis on corrosion resistance, mechanical properties, and biocompatibility. We screened experiments and papers that planned the application of magnesium fluoride coatings in living organisms. We have selected the literature with the aim of enhancing the performance of in vivo implants for reading and further detailed classification. The authors searched PubMed, SCOPUS, Web of Science, and other databases for 688 relevant papers published between 2005 and 2021, citing 105 of them. The selected time range is the last 16 years. Furthermore, this paper systematically discusses future prospects and challenges related to the application of magnesium fluoride coatings to medical products.

Zinc chloride hydroxide - A recyclable diffusion source for fabrication of zinc rich coatings on magnesium alloys

To reduce greenhouse gas emissions and fuel consumption, it is important to utilize lighter materials in vehicles. Magnesium is the lightest structural metal, but the corrosion resistance of magnesium and magnesium alloys is limited. The powder thermal diffusion alloying method can enhance the surface of magnesium alloys by fabricating a metallic coating. The huge consumption of powders and potential environmental pollution problems should be controlled for the sustainable development of related industries. Here, based on the investigation of the evolution of a diffusion source in powder thermal diffusion alloying processes, we propose a recyclable diffusion source that can be utilized in a series of diffusion alloying processes without reloading a new diffusion source or the addition of other powders. This diffusion source is mainly based on reversible chemical reactions related to zinc hydroxide chloride. With such a recyclable diffusion source, diffusion alloying processes can be carried out more fluently, and the powders can be saved effectively. Meanwhile, both the environment and the health of workers can be protected. It is our hope that this idea could inspire traditional pack cementation industries to find similar resource-conserving and environmentally friendly approaches. Meanwhile, widespread application of both magnesium alloys and zinc hydroxide chlorides can be promoted.

Preparation and properties of FHA coatings on micro-arc oxidised AZ91D magnesium alloy with different deposition times

ABSTRACT To improve the corrosion resistance of magnesium (Mg) alloy under the physiological environment, fabrication of fluoridated hydroxyapatite (FHA) coating on micro-arc oxidised AZ91D Mg alloy was carried out by electrochemical deposition. The influence of electrochemical deposition time on surface morphology, phase composition, electrochemical properties, and degradation behaviour of the FHA coating was studied by SEM, XRD, electrochemical testing, and in-vitro immersion test, respectively. The results of the electrochemical test and in-vitro immersion test show that FHA coating can significantly improve corrosion resistance. In particular, the sample with deposition time of 60 min showed the minimum corrosion current density (1.26 × 10−6 A cm−2), which may be attributed to a significant decrease in the imperfections of the coating being achieved after this optimum deposition time.

Влияние импульсного наносекундного лазерного излучения на коррозионную стойкость магниевого сплава системы Mg-Al-Zn

Влияние импульсного наносекундного лазерного излучения на коррозионную стойкость магниевого сплава системы Mg-Al-Zn

Effect of composite coating with poly-dopamine/PCL on the corrosion resistance of magnesium

ABSTRACTWe report the use of poly(ε-caprolactone) (PCL) and poly-dopamine (PD) as a protective coating that inhibits corrosion of the underlying magnesium metal. The PD coating layer also improved the adhesion of the PCL layer, which has been found to have a significant effect on corrosion behavior. In this study, electrochemical methods were employed to investigate the corrosion behavior of Mg after applying PCL composite coatings. Potentiodynamic polarization measurements determined that the PCL coating pretreated with PD effectively inhibited metal corrosion. In addition, the coating layer with improved adhesion has shown the possibility of inhibiting metal corrosion.

Microstructure and properties of AL-SI alloy cladding on AZ91D magnesium alloy by low heat input DC-PMIG welding

The corrosion resistance of magnesium is an important research field for useful application in industry. In order to form a corrosion resistant layer with enough thickness and strong adhesion on the surface of magnesium alloy, a low cost and efficient production process–direct current (DC) pulse metal inert gas (PMIG) welding was used to deposit Al-Si alloy on AZ91D magnesium matrix. The heat input was strictly controlled to form compact metallurgical coating with a maximum thickness of 1.8mm. The composite layer can be divided clearly into three zones: Mg matrix zone, the transition zone composed of a variety of intermetallic compounds (Al12Mg17, Al3Mg2 and Mg2Si etc.), and alloy coating (α-Al dendrites, Al-Si eutectic and Mg2Si.) zone. Furthermore, the properties of the alloy coating zone were investigated by both micro-hardness test and electrochemical corrosion. The micro-hardness of the coating is almost two times higher than that of the matrix and the corrosion resistance of the coating was greatly improved compared with that of the matrix.

Titanium dioxide coatings on magnesium alloys for biomaterials: A review

El magnesio y sus aleaciones, que aún se encuentran en desarrollo, se usan en aplicaciones ortopédicas debido a su biocompatibilidad y propiedades mecánicas (similares al hueso), que los hacen adecuados para aplicaciones en biomateriales. El magnesio tiene potencial para ser usado en implantes biodegradables dada su capacidad de soportar los procesos de regeneración de tejidos. En consecuencia, se han desarrollado varias estrategias para mejorar las propiedades del magnesio. Los recubrimientos sobre magnesio se emplean para mejorar su citocompatibilidad y resistencia a la corrosión. Específicamente, el dióxido de titanio se puede usar como recubrimiento protector sobre el magnesio, con el fin de ayudar a regular la velocidad de degradación y superar algunos problemas que se encuentran cuando el magnesio es implantado en el cuerpo. Por tanto, en este artículo se realizó una revisión crítica para consolidar la literatura disponible acerca de recubrimientos de dióxido de titanio sobre aleaciones de magnesio para potenciales aplicaciones en biomateriales. En este documento se hace énfasis en los recubrimientos obtenidos por medio de la de la ruta sol-gel como técnica prometedora para aplicaciones biomédicas.

Effect of high repetition laser shock peening on biocompatibility and corrosion resistance of magnesium

Magnesium, as a biomaterial has the potential to replace conventional implant materials owing to its numerous advantages. However, high corrosion rate is a major obstacle that has to be addressed for its implementation as implants. This study aims to evaluate the feasibility and effects of High Repetition Laser Shock Peening (HRLSP) on biocompatibility and corrosion resistance of Mg samples and as well as to analyze the effect of operational parameters such as peening with overlap on corrosion rate. From the results obtained using hydrogen evolution and mass loss methods, it was found that corrosion rates of both 0% overlap and 66% overlap peened samples reduced by more than 50% compared to that of unpeened sample and sample peened with 66% overlap exhibited least corrosion. The biocompatibility of peened Mg samples was also enhanced as there was neither rapid pH variation nor large hydrogen bubble formation around samples.

Eelectrochemical properties and corrosion resistance of carbon-ion-implanted magnesium

The corrosion resistance of magnesium-based biomaterials is critical to clinical applications. In this work, carbon as a biocompatible and benign nonmetallic element with high chemical inertness is implanted into pure magnesium to improve the corrosion behavior. X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), and Raman scattering reveal the formation of an amorphous carbon layer after ion implantation. Electrochemical studies demonstrate remarkable improvement in the corrosion resistance of magnesium in simulated body fluids (SBF) and Dulbecco’s Modified Eagle Medium (DMEM).

Research Progress on Organic Additives in the Anodic Oxidation Process of Magnesium and its Alloys

Magnesium and its alloys have excellent physical and mechanical properties for a number of applications. Unfortunately, magnesium and its alloys are highly susceptible to corrosion, which greatly restricts their further application. Anodic oxidation treatment is an effective method to improve the corrosion resistance of magnesium and its alloys. In the anodic oxidation process, organic additives have significantly effects on the performance of the oxide film. This paper reviews the research progress on organic additives, in order to provide some references for the research of the electrolyte in the anodic oxidation process of magnesium and its alloys.

Tratamientos químicos de conversión para la protección de magnesio biodegradable en aplicaciones temporales de reparación ósea

The present study was developed to improve the corrosion resistance of pure magnesium by applying chemical conversion coatings. Carbonate and fluoride layers were generated by immersion in solutions of NaHCO 3 of concentration 9 wt.%and HF of concentration 48 wt.%, respectively. Corrosion resistance of the coated samples was evaluated in comparison with that of the uncoated substrate by electrochemical techniques in a physiological solution (PBS). Results have shown that the carbonate coating is not viable to be used for protecting magnesium against corrosion.On the contrary, the fluoridemagnesiumcoating significantly increases the corrosion resistance ofmagnesium in physiological medium. The high compactness and adherence to the base metal of theMgF 2 layer produced by this simple chemical conversion treatment confer the protective properties to the coating.

Preparation of Mg-Yb alloy film by electrolysis in the molten LiCl-KCl-YbCl 3 system at low temperature

The electrochemical behavior of Yb 3+ and electrodeposition of Mg-Yb alloy film at solid magnesium cathode in the molten LiCl-KCl-YbCl 3 (2 wt.%) system at 773 K was investigated. Transient electrochemical techniques, such as cyclic voltammetry, chronopotentiometry and chronoamperometry were used in order to explore the deposition mechanism of Yb. The reduction process of Yb 3+ is stepwise reactions which are single-electron and double-electron reversible charge transfer reactions. The speed control step was a diffusion-controlled step which is caused by concentration polarization. The microstructures of Mg-Yb alloy film were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and EPMA area analysis. A very thin Mg 2Yb alloy film (∼200 nm) was formed by potentiostatic electrolysis at −1.85 V (vs. Ag/AgCl) for 12 h. A much thicker Mg 2Yb alloy film (∼450 μm) was obtained at −2.50 V (vs. Ag/AgCl) for 2.5 h. The corrosion resistance of magnesium can be enhanced by electrochemical formation of Mg-Yb alloy film on its surface.

アミノアクリル系樹脂被覆マグネシウム合金の耐食性に及ぼすシランカップリング処理の影響

Magnesium is a light metal with high specific strength and electromagnetic shielding properties. however, magnesium is inferior to corrosion resistance. For that reason, it is important to improve its corrosion resistance through surface treatments. Typical surface treatments of magnesium include conversion coating, anodizing and coating. Chromate coating is well known as one method that is limited to use for surface treatments because of its carcinogenicity. Coating processing is an effective method of improving magnesium corrosion resistance.This paper describes the effects of silane coupling treatment on the corrosion resistance of magnesium alloys by aminoacrylate system coating. To improve magnesium's corrosion resistance, we evaluated corrosion resistance of Mg(OH)2 coating, silane coupling treatment, and inorganic-organic composite coating with graded structures from substrates by conducting salt-spray testing (SST), along with perspiration-resistance, cross-cut, and boilproof tests.Results show that the high-corrosion resistance treatment with silane coupling + inorganic-organic composite coating (aminoacrylate system coating) on magnesium alloy was about 1000 hr by SST. In addition, corrosion resistance of silane coupling + inorganic-organic composite coating affected the coating thickness.

Corrosion resistance of magnesium treated by hydrocarbon plasma immersion ion implantation

Due to its low weight, magnesium is increasingly being used as construction materials for e.g. automobile bodies or cell phone housings. However, the material suffers from poor tribological features and particularly from poor corrosion resistance. In order to protect magnesium from corrosion, it was treated by hydrocarbon plasma immersion ion implantation. Magnesium samples were implanted with methane and acetylene at different process times at ambient temperature. Electrochemical corrosion measurements in dilute buffered acetic acid showed that the treatment led to well-adhering films with an effective corrosion protection.

Surface Modification of Magnesium with Rare Earth Conversion Films for Biomedical Protection

The specific gravity and elastic modulus of magnesium alloys are similar to that of human bone. Magnesium is one of the most important elements in the human body and plays a key role in the metabolic process. But the application of magnesium is seriously limited as a biomaterial since it corrodes easily in the physiological environment of the body. In order to reduce the corrosion, we developed protective films using rare earth (RE) conversion processing. The surface of magnesium samples was modified by contact with different rare-earth salt solutions; then the samples were dipped in SBF to test their corrosion resistance. The change of mass and the pH of the solutions were measured continuously using an electronic scale and a pH micrometer. The surface microstructure of the samples was observed by XRD and metallomicroscope. Corrosion rates of the samples in SBF were determined using Taffier curve. The preliminary results show that the conversion treatment with CeCl3 or Y(NO3)3 can improve the corrosion resistance of magnesium in SBF. The relationship of the RE salts concentration and the corrosion properties were studied,the best combination of parameters was determined, and the formation mechanism of rare-earth conversion film has been also elaborated.