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The corrosion resistance of a coating reflects its ability to protect the base metal and resist environmental degradation; it is an important indicator that directly affects the service life of metal components. In particular, for protective coatings and protective-decorative coatings, there are clear requirements regarding their corrosion resistance, and strict testing must be conducted. Corrosion tests include two categories: laboratory corrosion tests and field corrosion tests. Laboratory corrosion tests can be divided into liquid immersion corrosion at room temperature or under heating, gas corrosion (including high-temperature oxidation), as well as salt spray tests, among others. There are also various types of field corrosion tests, such as atmospheric corrosion, immersion in seawater and fresh water, soil corrosion, and coupon testing. Based on the nature of the corrosive medium, it can be further classified into types such as acidic, alkaline, and neutral salt corrosion. The corrosion test conditions shall be determined based on the technical standards of the test coating material or the operating conditions of that coating material. The pH value of the solution, the amount of dissolved gases, the concentration of dissolved ions, as well as the solution temperature and flow rate, all have a direct impact on the corrosion reaction of the coating. It is generally believed that the dissolved gases in a solution, particularly the oxygen content in neutral solutions, have a significant impact on the cathodic reactions involved in the corrosion process. Meanwhile, the temperature of the liquid affects not only the reaction rate but also the type of reaction that takes place.