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Both phosphating and passivation can improve the corrosion resistance of metal surfaces, but the composition and properties of the protective films formed are different. Phosphating is a process in which chemical and electrochemical reactions are used to form a phosphate-based chemical conversion coating; the resulting phosphate conversion coating is known as a phosphating coating. It is primarily used to improve the corrosion resistance of metal surfaces, by forming a water-insoluble crystalline phosphate film on the metal surface to protect the underlying metal from external environmental influences. Passivation is a method of converting the metal surface into a state that is less susceptible to oxidation, thereby slowing down the rate of metal corrosion. It primarily does this by using a passivator to form a dense passivation film on the metal surface; this film effectively prevents external corrosive agents from attacking the metal beneath it. When applying anti-corrosion treatment to galvanized parts, whether to use phosphating or passivation depends on the specific operating environment and requirements. Phosphating is an effective method for metal corrosion protection. It improves the corrosion resistance of metal surfaces by forming a phosphate conversion coating on them. The phosphating film possesses good corrosion resistance, wear resistance, and lubricity, and can effectively improve the fatigue resistance and friction-reducing properties of metals. In comparison, passivation is a more effective anti-corrosion treatment method. For galvanized parts that need to be exposed to corrosive environments for extended periods, passivation can provide more durable protection by forming a dense passivation film on the metal surface, which effectively prevents external corrosive agents from attacking the underlying metal. What are the respective corrosion protection durations for phosphating or passivating galvanized parts? The phosphating coating alone cannot provide effective rust protection; its rust-resistant properties can only be improved by combining it with subsequent processes such as painting, and the degree of improvement is quite small. Furthermore, the phosphating film has a certain degree of brittleness; it is prone to cracking under impact, allowing corrosive agents to penetrate and cause surface corrosion. Therefore, the corrosion resistance duration of the phosphating film depends on factors such as its operating environment, working conditions, and degree of impact. Under normal conditions, the corrosion-resistant lifespan of a phosphating coating is generally several months to about one year. In harsh operating environments, such as high humidity, high temperatures, and high impact, the corrosion resistance period may be shortened. To extend the corrosion resistance of the phosphating coating, painting or other surface treatments such as spraying paint or applying oil can be carried out after the phosphating process. These surface treatments can provide additional corrosion protection and improve the efficiency of the entire anti-corrosion system. The corrosion resistance duration of galvanized parts after passivation depends on various factors, including the quality of the passivation treatment, the operating environment, working conditions, and degree of exposure to impacts. Generally, after high-quality passivation treatment, galvanized parts can maintain their corrosion resistance for several decades. However, in harsh operating environments such as high humidity, high temperature, and high impact, the corrosion resistance period may be shortened. Furthermore, if the quality of the passivation treatment is poor, or if the galvanized parts are damaged by external factors during use, such as scratches or impacts, this will also affect their corrosion resistance. To extend the corrosion protection duration of galvanized parts through passivation treatment, certain measures can be taken, such as improving quality control, conducting regular maintenance, and avoiding scratches and impacts. These measures can improve the efficiency of the entire anti-corrosion system and extend the anti-corrosion lifespan of galvanized parts.