Treatment method for alloying surface of magnesium alloy workpiece

The invention discloses a magnesium alloy workpiece surface alloying treatment method which comprises the following steps: step 1, polishing the surface of a magnesium alloy workpiece, cleaning a pure copper target material and the magnesium alloy workpiece of which the surface is polished to remove oil stains, and standing for later use after cleaning; 2, the magnesium alloy workpiece treated in the step 1 and a pure copper target material are placed in a machining chamber of an electron beam welding machine, the electron beam welding machine is vacuumized, the surface of the magnesium alloy workpiece is subjected to copper plating treatment through the electron beam welding machine, and a copper-plated magnesium alloy workpiece is obtained; and 3, the copper-coated magnesium alloy workpiece obtained in the step 2 is placed in a machining chamber of an electron beam machine, the electron beam machine is vacuumized, the surface of the copper-coated magnesium alloy workpiece is subjected to alloying treatment