Comparison of Corrosion Resistance and Cytocompatibility of MgO and ZrO2 Coatings on AZ31 Magnesium Alloy Formed via Plasma Electrolytic Oxidation

Abstract

In this work, one coating is comprised of ZrO 2 and the other consists of MgO as main phase composition was produced on AZ31 magnesium alloy using one-step plasma electrolytic oxidation (PEO). The purpose of this work was to study the corrosion resistance and cytocompatibility of the above-coated AZ31 magnesium alloys in order to provide a basis for AZ31 Mg alloy's clinical applications of biomedical use. The morphology and phase composition of the coatings were studied using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The corrosion properties were examined using electrochemical testing, hydrogen evolution measurements, and immersion tests in a simulated body fluid (SBF). Compared with bare magnesium and the MgO coating, the ZrO 2 -containing coating exhibited an improved corrosion resistance. Cell proliferation assays and cell morphology observations showed that the ZrO 2 -containing coating was not toxic to the L-929 cells. The ZrO 2 coating was much denser and more homogeneous than the MgO coating, hence the corrosion resistance of the ZrO 2 -coated AZ31 Mg alloy was superior and more stable than the MgO-coated AZ31 Mg alloy, and ZrO 2 /AZ31 did not induce a cytotoxic reaction to L-929 cells and promote cell growth.

Influence of Complex SiF62− Ions on the PEO Coatings Formed on Mg–Al6–Zn1 Alloy for Enhanced Wear and Corrosion Protection

“…The noble properties also have a deep link with the phases present in the coatings. As reported earlier that presence of undissolved MgF 2 thin film formed in the initial stages of PEO could prevent the corrosion ions (Cl − ) penetrating through the PEO films to corrode the Mg substrate [7]. For comparison, the tafel curve of bare AZ61 can also be seen in Figure 6.…”

“…Using PEO process, hard ceramic coatings can be formed on various kinds of light metal alloys using appropriate solutions and additives such as alkaline silicates, phosphates, etc. Though the PEO coatings have comparable mechanical properties, due to porosity and defect issues, however, the coatings need further improvement in regards to corrosion protection, for long-term applications [1][2][3][4][5][6][7].…”

A Novel Processing for CNT-Reinforced Mg-Matrix Laminated Composites to Enhance the Electromagnetic Shielding Property

“…Magnesium possess low density, high specific stiffness, high specific strength, excellent damping capacity, recyclability, and easy fabrication [14][15][16] while also possessing good electromagnetic shielding property [5]. At present, most of the researches on the electromagnetic shielding properties of magnesium with rare earth (RE) have already been carried out [3,5,9,17,18].…”

Influence of Cu2+ Ions on the Corrosion Resistance of AZ31 Magnesium Alloy with Microarc Oxidation

“…Metallic biomaterials are widely used in dentistry, orthopedics, and cardiovascular medicine [4,5]. Given their biological stability and excellent mechanical and processing properties, metallic biomaterials play an important role in implant applications [6][7][8]. Implants are used to reconstruct a failed tissue; therefore, a traditional biomaterial frequently requires a second surgery for removal [2].…”