Bio-corrosion characterization of Mg–Zn–X (X = Ca, Mn, Si) alloys for biomedical applications

• Published in: Journal of materials science. Materials in medicine Vol. 21; no. 4; pp. 1091 - 1098
• Main Authors: Rosalbino, F., De Negri, S., Saccone, A., Angelini, E., Delfino, S.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.04.2010; Springer; Springer Nature B.V
• Subjects: Alloys - chemistry; Applied sciences; Biocompatible Materials - chemistry; Biocompatible Materials - metabolism; Biological and medical sciences; Biomaterials; Biomedical Engineering and Bioengineering; Biomedical materials; Biomedical Technology - instrumentation; Biomedical Technology - methods; Body Fluids - metabolism; Body Fluids - physiology; Calcium - chemistry; Ceramics; Chemistry and Materials Science; Coated Materials, Biocompatible; Composites; Corrosion; Exact sciences and technology; Glass; Magnesium; Magnesium - chemistry; Manganese - chemistry; Materials Science; Materials Testing; Medical sciences; Metals. Metallurgy; Models, Biological; Natural Materials; Orthopedics; Polymer Sciences; Prostheses and Implants; Regenerative Medicine/Tissue Engineering; Silicon - chemistry; Surface Properties; Surfaces and Interfaces; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology. Biomaterials. Equipments; Thin Films; Transplants & implants; Zinc - chemistry; Magnesium Alloy; Electrochemical Impedance Spectroscopy; Potentiodynamic Polarization; AZ91 Alloy; Polarization Resistance; Biological fluid; Calcium; Corrosion; Implant; Magnesium alloy; Biomaterial; Silicon; Zinc alloy; Biomedical engineering; Manganese
• ISSN: 0957-4530; 1573-4838
• DOI: 10.1007/s10856-009-3956-1

The successful applications of magnesium-based alloys as biodegradable orthopedic implants are mainly inhibited due to their high degradation rates in physiological environment. This study examines the bio-corrosion behaviour of Mg–2Zn–0.2X (X = Ca, Mn, Si) alloys in Ringer’s physiological solution that simulates bodily fluids, and compares it with that of AZ91 magnesium alloy. Potentiodynamic polarization and electrochemical impedance spectroscopy results showed a better corrosion behaviour of AZ91 alloy with respect to Mg–2Zn–0.2Ca and Mg–2Zn–0.2Si alloys. On the contrary, enhanced corrosion resistance was observed for Mg–2Zn–0.2Mn alloy compared to the AZ91 one: Mg–2Zn–0.2Mn alloy exhibited a four-fold increase in the polarization resistance than AZ91 alloy after 168 h exposure to the Ringer’s physiological solution. The improved corrosion behaviour of the Mg–2Zn–0.2Mn alloy with respect to the AZ91 one can be ascribed to enhanced protective properties of the Mg(OH) 2 surface layer. The present study suggests the Mg–2Zn–0.2Mn alloy as a promising candidate for its applications in degradable orthopedic implants, and is worthwhile to further investigate the in vivo corrosion behaviour as well as assessed the mechanical properties of this alloy.