Ball flower like manganese, strontium substituted hydroxyapatite/cerium oxide dual coatings on the AZ91 Mg alloy with improved bioactive and corrosion resistance properties for implant applications

摘要

Bio-degradable metals and alloys have been suggested as revolutionary potential materials for bone-related treatment. Of these materials, the AZ91 magnesiumalloy (AZ91 Mg alloy) emerges as an attractive candidate due to its non-toxicity and outstanding mechanical properties. Even though magnesium alloys are widely studied as orthopedic implants for bone replacement and bone regeneration, their undesirable rapid corrosion rate under physiological conditions has limited their actual clinical applications. Therefore, increasing the corrosion resistance of the AZ91 Mg alloy is one of the key issues to address for the development of bio-degradable implants. In this study, a cerium oxide (CeO2) coating is developed on the AZ91 Mg alloy by electrodeposition with a view of minimizing its corrosion rate during the bone healing period. Further, to improve the clinical application of AZ91 Mg alloy, manganese (Mn) and strontium (Sr) substituted hydroxyapatite (Mn, Sr-HAP) coatings were developed on the CeO2 coated AZ91 Mg alloy. Hence, this study reports on the development of a Mn, Sr-HAP/CeO2 dual coating on the AZ91 Mg alloy to make it a suitable alternative material for orthopedic implants.