Influence of yttrium element on the corrosion behaviors of Mg–Y binary magnesium alloy

The influence of yttrium on the corrosion behavior of Mg–Y alloys has been investigated by electrochemical measurements, scanning electron microscope (SEM) observation, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analysis in NaCl solution. The corrosion resistance decreased with increasing Y content due to increasing Y-rich zone. The solid-dissolved Y improved the chemical activity of the substrate which promoted the corrosion reaction by forming Y2O3. The corrosion resistance was improved by increasing the Y concentration of matrix and proper net Y-rich structure. The sample has the best corrosion resistance when all the Y element was dissolved into the matrix of Mg–5Y in 0.1 M NaCl.