Method for the anti-corrosion treatment of a magnesium alloy part, corresponding anti-corrosion substance and treated part

A method for anti-corrosion treatment of a magnesium alloy part, the method comprising bringing a portion of the part, at least locally, into contact with an anti-corrosion substance for a predetermined period, using an applicator member,

• wherein the anti-corrosion substance contains:
• permanganate ions MnO4−;
• dihydrogen phosphate ions H2PO4−;
• and
• an epoxy gel, the pH of which is between 6 and 8,
• after mixing, the anti-corrosion substance comprising a molar concentration of permanganate ions [MnO4−] greater than or equal to 0.06 mol/L (moles per liter) and less than or equal to 0.31 mol/L, and a molar concentration of dihydrogen phosphate ions [H2PO4−] greater than or equal to 0.47 mol/L (moles per liter) and less than or equal to 0.63 mol/L, and preferably between 0.51 mol/L and 0.59 mol/L,
• and wherein, after the predetermined period, the method comprises rinsing the portion of the part with water.