Enhancement of the corrosion resistance of Molybdenum by La₂O₃ dispersion

The corrosion behavior of pure Molybdenum (Mo) and Mo doped with 0.3 wt.% La₂O₃ was investigated in aerated 3.5 wt.% NaCl at 25 °C. Compared with the pure Mo, the doped Mo exhibits significantly increased corrosion resistance, with a smaller current density during anodic polarization and a 2∼3 times larger charge transfer resistance. Such an enhancement originates from the refinement of grains and purification of the grain boundary due to the addition of La₂O₃, which facilitates the formation of a compact and protective oxide film. Our results provide a recipe to improve the corrosion resistance of Mo alloys.