Tuning bioactivity and degradation behavior of magnesium implants using wollastonite embedded plasma electrolytic oxidation coatings

Magnesium alloys used as biodegradable implants require enhanced bioactivity and corrosion resistance in physiological media. This study investigated the bioactivity and degradation behavior of plasma electrolytic-oxidized magnesium coatings incorporating different amounts of biocompatible wollastonite particles. The findings revealed that the interference of wollastonite particles in the layer formation interactions caused a drop in the formation voltage, resulting in a reduction in the oxide layer thickness and an increase in the surface roughness. Incorporating wollastonite particles into the oxide layer induced more calcium phosphate deposits during immersion in simulated body fluid, indicating enhanced bioactivity. The biodegradation evaluation revealed that the corrosion rate of the oxide layer was increased from ۰.۵۸۸ to ۳.۲۲۹ mm.year-۱ with the embedment of ۴.۵ g.L-۱ wollastonite particles, which resulted from the weakening of the structural compaction based on the electrochemical impedance spectroscopy. Therefore, wollastonite particles are a suitable option to improve the bioactivity of plasma electrolytic-oxidized magnesium coatings and provide a degradation rate suitable for biological media.

کلیدواژه ها:

Plasma electrolytic oxidation ، Magnesium ، Wollastonite ، Bioactivity ، degradation