AZ31 Mg Foams Coated with Collagen Solutions: Corrosion Evaluation in a Simulated Environment of Physiological Conditions

Abstract AZ31 magnesium alloys stand out as a pivotal alternative for orthopedic applications owing to their inherent attributes of biocompatibility, biodegradability, favorable mechanical properties, and the facilitation of bone regeneration. The Mg AZ31 foams serve as temporary implants thanks to its bioabsorbability, offering the advantage of obviating the need for additional surgical interventions and minimizing associated ailments and discomfort. However, addressing the intrinsic corrosion rate of magnesium is imperative. To mitigate corrosion, surface activation techniques, specifically alkaline activation and hydrofluoric activation, are applied to treat the surfaces of AZ31 alloys. Subsequently, these treated alloys, configured as scaffolds, undergo coating with varying concentrations of collagen solutions (0%, 16%, and 64% w/w). The corrosion rate is then assessed through the hydrogen evolution method within a simulated physiological environment (simulated body fluid [SBF]). The analysis of results employs quantitative techniques, such as atomic absorption (AA) spectroscopy and qualitative methods, including electron microscopy with atomic analysis. The outcomes reveal the successful consolidation of the collagen coating, identification of corrosion byproducts, a notable reduction in corrosion rate, and additional indicators providing evidence of potential bone tissue regeneration.