Approved and commonly used metallic biomaterials include stainless steels, titanium, and cobaltchromium-based alloys. A limitation of these current metallic biomaterials is the possible release of toxic metallic ions and particles through corrosion or wear processes. The elastic module of these metallic biomaterials is not well matched with that of natural bone tissue, resulting in stress shielding effects that can lead to reduced stimulation of new bone growth and remodelling which decreases implant stability.
Magnesium and its alloys hold significant potential for becoming the default alternative to mainly used metallic biomaterials due to its biodegradable property, biocompatibility, and suitable mechanical property. Magnesium is the eighth most abundant element in the earths crust and non-toxic to the natural environment and human body. These serious advantages encourage intensive scientific studies for the use of magnesium alloys as implants.
The corrosion behavior of Mg-AZ61 has been evaluated in simulated body fluid (SBF) solution using a special programme via linear polarization method (LPR) for 6 hours and the corrosion products on the metal surface after electrochemical assessments were also investigated using an optical microscope. In this study, the importance of the long-term electrochemical methods and the appropriate time for the measurement has been emphasised for the rapidly corroding metals such as magnesium. The polarization resistance obtained at the end of one hour was 124 Ω cm2, while at the end of 6 hours this value was 736 Ω cm2 due to the effect of the oxide film formed on the metal surface.
Anahtar Kelimeler: Corrosion, Magnesium, AZ61, Linear polarization