Research Progress of Surface Protection and Spraying Technology on Aluminum Alloy

Aluminum alloys have been widely used in automotive, rail transportation, aerospace and 5G communications due to their high specific strength, superior ductility and excellent thermal conductivity. However, their low surface hardness, poor abrasion resistance and susceptibility to corrosion limit the application of aluminum alloys in environments with complex loads and corrosive conditions. One of the methods to enhance the wear resistance and corrosion resistance of aluminum alloy is to prepare a protective layer on its surface using spraying technologies. The research progress of spraying technologies for aluminum alloy surfaces was reviewed, primarily focusing on plasma spraying, arc spraying, high velocity oxygen(air) fuel spraying and cold spraying. The internal defects, bonding strength, wear resistance and corrosion resistance of the coatings prepared by these techniques on aluminum alloy surface were compared, the advantages, disadvantages and applicable scenarios of each spraying technology for coating preparation on aluminum alloys were summarized, and the existing problems and the solutions of spraying technologies in the preparation of coatings were pointed out. Finally, the future development directions for spraying technologies on aluminum alloy surface were discussed.