The corrosion of metal material in the intermediate of sea, lake or soil can be prevented be the using of electric cheminology cathode protection.

Magnesium anode is used in this method. Its theory is connect the current of more negative. metal material or alloy with the protected metal body, with the exhaustiong and dissolving of negative matel material or alloy, protective current is transfused to protected metal body, this metal body will be protected from corrosion. It is widely used in ship building, port construction, sea work, underearth pipeline, oil chemical, electricity and other area.