A probe into the corrosion behavior of a WE43B magnesium alloy in a simulated body fluid using dynamic electrochemical impedance spectroscopy

WE43B is one of the newest Mg alloys with practical application in biomedical implant technology. This work attempts to scrutinize the corrosion characteristics of WE43B alloy in a simulated body fluid (SBF) at a typical body temperature. The dynamic-electrochemical impedance spectroscopy with the capacity to track changes on surfaces in a dynamic corrosive system is used in combination with other classical techniques namely, linear polarization, EIS, and hydrogen evolution to track the corrosion pattern of the alloy in SBF for 24 h. The electrochemical results reveal a steady increase in the corrosion resistance of the alloy with immersion time reaching 1398 Ω cm2 at 24 h. This corroborates the hydrogen evolution results in which a declining trend in the corrosion rate with immersion time is observed. The corrosion rate of the alloy is in the range of 1.326-1.338 mm y−1 at 24 h. The results from the applied techniques are comparable. The surface analysis (scanning electron microscope, energy-dispersive x-ray spectroscopy, atomic force microscopy AFM) results conform with the results obtained from applied methods.