Attain insensitivity to chlorine ions in magnesium alloys by impeding the diffusion process

Abstract

To serve in a more aggressive chlorine (Cl−) ions-containing environment, a chlorine ions insensitivity Mg-Nd-Zr alloys is fabricated, exhibiting a stable corrosion resistance in either 3.5wt.% or 10 wt.% NaCl solution. Unlike pure Mg who exhibit a negligible protection of the matrix, a distinct “hindering effect” of Cl− diffusion caused by doping elements within the corrosion film was observed. Its underlying mechanism is demonstrated by X-ray photoelectron spectroscopy (XPS) and Density functional theory (DFT) analysis. The introducing with Nd and Zr elements can effectively passivate vacancies and alter diffusion energy of chlorine ions.