Thermodynamics and kinetics of phase transformation in rare earth–magnesium alloys: A critical review

Advances in functionalized polymer coatings on biodegradable magnesium alloys - A review.

Advances in coatings on biodegradable magnesium alloys

Recent advances in hybrid organic-inorganic materials with spatial architecture for state-of-the-art applications

Recent advances in biodegradation controls over Mg alloys for bone fracture management: A review

Layered double hydroxide coatings on magnesium alloys: A review

Regulating degradation rate and moderate pH micro-environment for biodegradable magnesium alloys face huge challenge. The chemical and morphological characteristics of micro-arc oxidation (MAO) and chitosan (CS) composite coatings, fabricated on Mg-4Li-1Ca alloy, are analyzed through field-emission scanning electronic microcopy, energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Corrosion resistance of the samples is evaluated via hydrogen evolution, potentiodynamic polarization and electrochemical impedance spectroscopy in Hank's solution. Results indicated that the MAO and CS coating enhances the corrosion resistance and antibacterial growth activity. With increasing immersion time, the degradation of the MAO/CS coatings gives rise to a decrease in pH value and leads to a rapid increase in hydrogen evolution rate after an immersion in Hank's solution after 100 h. The MAO/CS coatings retain the solution pH at a moderate level (less than or equal to 8.25). A novel self-degradation mechanism of the MAO/CS coating on Mg-Li-Ca alloy is proposed due to the fact that MAO/CS coating is cathodic relative to the substrate.

Self-degradation of micro-arc oxidation/chitosan composite coating on Mg-4Li-1Ca alloy

The present work aimed at assessing the electrochemical behavior and the corrosion inhibition performance of Mg-Al-layered double hydroxide (LDH) coatings modified with methyltrimethoxysilane (MTMS) and cerium nitrate on AA5005 aluminum alloy. The chemical compositions and surface morphologies of the coatings were investigated by XRD, FT-IR and FE-SEM, while their corrosion resistance was evaluated by electrochemical and immersion tests. An optimum corrosion resistance of the composite coatings was obtained by adding 10−2 mol·L−1 cerium nitrate. An excess addition of cerium nitrate resulted in a loose structure and poor corrosion resistance of the coating. The corrosion mechanism of the composite coatings was proposed and discussed.

Corrosion resistance of a silane/ceria modified Mg-Al-layered double hydroxide on AA5005 aluminum alloy

The invention provides a preparation method for a magnesium/magnesium alloy microarc oxidation-tantalum oxide composite coating. The preparation method comprises the steps of preparation of a magnesium/magnesium alloy microarc oxidation ceramic layer, atomic layer deposition pretreatment and atomic layer deposition for preparation of a composite layer. Main raw materials of a microarc oxidation electrolyte comprise phytic acid, sodium hydroxide and glucose. Main raw materials of atomic layer deposition comprise tris(diethylamino)(tert-butylimino)tantalum, ultrapure water, hydrogen peroxide, oxygen and ozone. The microarc oxidation ceramic layer of a porous structure is deposited on the surface of a magnesium/magnesium alloy substrate first through a microarc oxidation method, the chemicalcomponent of the microarc oxidation ceramic layer is mainly magnesium oxide, and then the composite coating of tantalum oxide is deposited through atomic layer deposition technology. The preparation process is simple, the film is easy to control, the obtained composite coating has the characteristics of being compact in structure, high in adhesive force, good in corrosion resistance and biocompatibility and the like, and the preparation method can be used for protection of magnesium/magnesium alloy and particularly suitable for implantable biomaterials.

Yong-Feng Zhou

Papers

Layered double hydroxide coatings on magnesium alloys: A review

Self-degradation of micro-arc oxidation/chitosan composite coating on Mg-4Li-1Ca alloy

Corrosion resistance of a silane/ceria modified Mg-Al-layered double hydroxide on AA5005 aluminum alloy

Preparation method for magnesium/magnesium alloy microarc oxidation-tantalum oxide composite coating