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The so-called full-immersion corrosion resistance test is a corrosion test in which the painted sample is continuously immersed (with periodic removal for observation or testing) in a container containing a corrosive solution. The so-called intermittent corrosion resistance test is a corrosion test in which painted samples are alternately immersed in a corrosive solution and exposed to the atmosphere. Comparing these two corrosion resistance tests, the latter often has sufficient oxygen during the dry-wet cycling process to eliminate or reduce cathodic protection, and it also makes it easier for the film formed by corrosion products to be damaged. Therefore, the interdip corrosion rate is generally much faster than that of full immersion corrosion. The purpose of conducting full immersion or partial immersion corrosion resistance tests is to scientifically determine the corrosion resistance of the coating film. Typically, the painted sample (or rod) is fully or partially immersed in a solution containing a corrosive medium (such as saltwater, seawater, solvents, acids, bases, actual production solutions, etc.), either at a controlled temperature or without such control; after a certain period of time, the changes in the paint film are measured. It is used to evaluate the corrosion resistance of the coating film. When evaluating the corrosion resistance of the coating film, first, visually inspect (or observe using a high-power magnifier) the changes in the appearance and color of the coating film on the painted test panels after full or partial immersion for a certain period of time, as well as any signs of bubbling or peeling, as well as the number, size, and density of bubbles. It is used to qualitatively evaluate the corrosion resistance of the coating film. Then, the corrosion resistance of the coating film can be quantitatively evaluated by measuring changes in the weight of the sample after full immersion or partial immersion for a certain period of time, as well as changes in its mechanical properties or other characteristics. In industrial anti-corrosion coating applications, the corrosion conditions are severe and variable; therefore, preliminary conclusions can only be drawn based on corrosion resistance test results from full immersion or partial immersion tests lasting more than 6 months.