Aluminum extrusions are alloy materials primarily composed of aluminum, obtained by melting aluminum rods and then extruding them into various cross-sectional shapes. However, the proportion of the alloy added varies, resulting in different mechanical properties and application fields for the industrial aluminum extrusions. What should be noted during the oxidation and post-processing of aluminum extrusions?

(1) Hot Water Rinse. The purpose of hot water washing is to age the film layer. However, both the water temperature and time must be strictly controlled, as excessive temperature can thin the film layer and fade the color. Over-processing aluminum profiles can also lead to similar issues. The recommended temperature and time are: 40-50℃ for 0.5-1 minute.

(2) Drying: It is best to dry naturally. The workpieces soaked in hot water should be hung diagonally on a rack, allowing the free water on the work surface to flow downwards in a straight line. The water droplets at the bottom corner should be absorbed with a towel. The film dried in this manner maintains its color and appears natural.

(3) Aging. The aging method for aluminum profiles can be determined based on climatic conditions. During the sunny summer, they can be exposed to sunlight; in rainy or winter weather, they can be baked in an oven. The process conditions are: temperature 40-50°C, time 10-15 minutes.

(4) Repair of Unqualified Parts: Unqualified conductive oxide film parts should be picked out before the drying and aging process, as the film layer is more difficult to remove after drying and aging, which may affect the surface roughness of the workpiece. The author has conducted some exploration in the process, and after testing various methods, found that the following method is very effective; it is simple and does not affect the surface quality of the workpiece.