The rust prevention process for aluminum alloy rotating racks (four layers) requires a combination of material properties and environmental adaptability, employing multi-layered technical methods to achieve long-term corrosion resistance. Aluminum alloys possess a certain degree of rust resistance due to the naturally formed alumina film on their surface; however, this film is only 0.1 micrometers thick and easily damaged, especially in humid, acidic, alkaline, or salt spray environments, necessitating enhanced protection through artificial intervention. The rust prevention process encompasses four core stages: surface pretreatment, coating application, chemical conversion, and environmental control.
Surface pretreatment is the foundation of the rust prevention process, directly affecting coating adhesion and durability. During the processing of aluminum alloy rotating racks (four layers), oil, metal debris, or oxide layers may remain on the surface, requiring degreasing and cleaning to remove impurities. Traditional processes use dilute hydrochloric acid pickling, but this presents environmental concerns. Currently, organic acid rust removers or biodegradable environmentally friendly cleaning agents like VCI-600E are commonly used, effectively removing rust without damaging the substrate. After pretreatment, surface neutralization is necessary, using a weak alkaline cleaning solution to remove residual acid and prevent subsequent corrosion of the metal. Coating is a key method for rust prevention, blocking contact with corrosive media through physical barriers. Electrophoretic coating and electroplating are common processes for aluminum alloy rotating racks (four layers). Electrophoretic coating involves mixing pigments, diluents, and surfactants and applying the mixture to the surface to form a uniform anti-corrosion layer of 5-25 micrometers, offering strong corrosion resistance and long-lasting gloss. Electroplating, on the other hand, involves electrolytically depositing a metal film with a thickness of 3-200 micrometers, resulting in a smooth, wear-resistant surface with customizable colors. Additionally, spraying rust-preventive paint or oil is a simple and effective method, especially suitable for temporary protection or low-cost applications.
Chemical conversion treatment enhances corrosion resistance by generating a dense protective film. Passivation is a typical application for aluminum alloy rotating racks (four layers), and is available in three types: trivalent chromium, hexavalent chromium, and chromium-free passivation solutions. After passivation, a passivation film forms on the aluminum surface, which can withstand neutral salt spray for 24-240 hours, equivalent to more than two years without oxidation. Phosphating enhances corrosion resistance by forming a phosphate protective layer, but requires strict control of the phosphating solution concentration and temperature. Anodizing is another important process, placing the aluminum alloy in an electrolyte solution as the anode, and generating a 5-20 micrometer alumina film through hydrolysis, offering significantly better corrosion resistance than natural oxide films.
Environmental control is a supplementary measure to rust prevention, especially suitable for warehousing and transportation. Aluminum alloy rotating racks (four layers) must be stored in a dry warehouse with relative humidity below 70%, avoiding co-storage with acids, alkalis, and salts. When stacking, the bottom of the stack should be elevated to improve ventilation and prevent water accumulation. During transportation, highly absorbent desiccants or VCI vapor phase rust inhibitors can be used, forming a protective film in a confined space through vapor phase rust prevention, effectively isolating oxygen and moisture.
Rust prevention in special environments requires targeted optimization. In coastal or high-humidity areas, aluminum alloy rotating racks (four layers) require more corrosion-resistant coatings, such as epoxy resin or polyurethane coatings, and increased coating thickness. For applications involving contact with chemicals, a protective shield should be added outside the coating, or a chemically resistant alloy material should be used. Regular inspection and maintenance are equally important; any coating damage or rust should be repaired promptly to prevent the spread of corrosion.
The rust prevention process for aluminum alloy rotating racks (four layers) forms a complete protective system through surface pretreatment, coating coverage, chemical conversion, and environmental control. From degreasing and cleaning to passivation, from electrophoretic coating to anodizing, each step is designed specifically for the characteristics of aluminum alloy and the operating environment, ensuring long-term stable operation of the rack in humid, acidic, alkaline, or salt spray environments, extending its service life and reducing maintenance costs.
