The reason why the surface of industrial aluminum profiles yellows
August 17, 2023
As we all know, industrial aluminum profiles belong to alloy extrusion materials, and it is easy to damage the material and surface defects of the profiles due to improper operation of one step in the production and processing process. Under normal circumstances, the surface color of industrial aluminum profiles should be silver-white, in addition to the surface roughness is not smooth, sometimes there will be yellowing phenomenon, the following content YueFeng Aluminum for you to sort out the reason for the surface yellowing phenomenon of industrial aluminum profiles:
The reasons for yellowing on the surface of industrial aluminum profiles can be roughly summarized into two kinds, one is the improper way used in the extrusion process of profiles, and the second is the improper surface treatment process of profiles. Specific analysis can refer to the following content:
1, the profile needs to be cooled after extrusion molding, in order to improve the mechanical properties and physical properties of the material. Coolant is used in its cooling process, and the coolant effect is different for different materials. Common coolants are water or oil-based coolants. If water is used for cooling or when the copper content of the coolant is relatively high, it will lead to yellowing of the surface of the profile. The reason for this is that the nature of aluminum is relatively active, and it is easy to react with the material in the air or water after contact.
2, the surface of the industrial aluminum profile is usually covered with a layer of oxide film, which can not only increase the corrosion resistance of the profile but also increase the beauty of the profile. However, before the surface treatment of the profile, it is necessary to clean the surface of the extruded profile to fully remove the oil on the surface. If the cleaning work in this step is not in place, it will cause the oxide film to be difficult to color in the subsequent oxidation process, or the coloring is not uniform enough, resulting in yellowing.
