Oxidation method of magnesium and magnesium alloy

The invention discloses an oxidation method of magnesium and a magnesium alloy. The method comprises the following steps that step1, a solution is prepared by comprising potassium chromate with the concentration of 20-30 g/L and ammonium phosphate aqueous with the concentration of 20-30 g/L to be used as an electrolyte, and the pH value of the electrolyte is adjusted to be 5.3-5.7; step 2, the magnesium or the magnesium alloy and a lead plate are correspondingly arranged in the electrolyte correspondingly, the magnesium or the magnesium alloy material is used as an anode, the lead plate is used as a cathode to carry out electrolytic reaction so as to oxidize the magnesium or the magnesium alloy material, wherein an electrolysis reaction condition is that the voltage of a power supply is 5-10 V, the current is 0.5-2.5 A/dm2, the temperature of the electrolyte is 20-25 DEG C, and the electrifying time is 5-15 minutes, and the magnesium or the magnesium alloy material with a membrane layer is obtained. According