The process of removing impurities attached to the surface of magnesium ingots and adding an anti-oxidation film layer. Magnesium is one of the metals with poor corrosion resistance, and the surface of magnesium ingots is easily corroded when exposed to the atmosphere. In addition, some impurities such as inorganic chlorine salt flux and electrolytes adhered to the surface of magnesium ingots will also strongly corrode magnesium. Therefore, magnesium ingots produced from refining must undergo appropriate surface protection treatment to reduce corrosion losses during storage. The method of surface treatment of magnesium ingots varies with the length of storage and user requirements.

Magnesium ingot appearance requirements: flat surface, smooth and shiny, no black oxidation spots, no obvious shrinkage holes

From an environmental perspective, it is better to pickle magnesium with sulfuric acid because nitric acid will produce gaseous nitrogen oxides and pollute the atmosphere.

　　Pickling process

　　1. Pickling preparation:

　　1.1 Tool preparation: crane, stainless steel cage, pickling tank, sulfuric acid;

　　1.2 Safety preparation: rubber gloves, safe distance

　　2. With acid:

　　2.1 Clean the entire pickling pool with clean water several times to ensure that there is no garbage, debris, or dust in the pool;

　　2.2 Fill the clear pool with water to three-quarters;

　　2.3 Fill the pickling tank with water and prepare the pickling liquid according to the corresponding proportion standards to three-quarters of the pickling tank;

　　3. Install ingots:

　　3.1 Place the stainless steel cage on the cart;

　　3.2 Install magnesium ingots into the stainless steel cage;

　　3.3 Push the cart under the overhead crane;

　　3.4 Start the crane, lift the stainless steel cage, and slowly move it to the pickling tank.