As we all know, industrial aluminum profile belongs to the alloy extrusion material, in the production and processing process is very easy due to a step of improper operation will lead to material damage and profile surface defects. Under normal circumstances, the surface color of industrial aluminum profile should be silver white, in addition to the surface roughness is not smooth, sometimes there will be yellowing phenomenon, about the industrial aluminum profile surface yellowing phenomenon causes:
Industrial aluminum profile surface yellowing reasons
Industrial aluminum profile surface yellowing reasons can be roughly summarized as two kinds, one is the profile in the extrusion process used in the improper way, the second situation is the profile surface treatment process is improper. Specific analysis can refer to the following content:
1, the profile after the die extrusion molding needs to be cooled, the purpose is to improve the mechanical properties of the material as well as physical properties. In its cooling process will be used to coolant, different materials use different coolant effect. Common coolant is generally water or oil-based coolant. If water is used for cooling or when the copper content in the coolant is relatively high, it will lead to the yellowing of the surface of the profile. The reason for this is that the nature of this metal aluminum is more active, easy to contact with the air or water is the material after the chemical reaction.
2, industrial aluminum profile surface is usually covered with a layer of oxide film, not only can increase the corrosion resistance of the profile can also increase the beauty of the profile. But before the surface treatment of the profile needs to be extruded on the surface of the profile for surface cleaning, fully remove the oil on the surface. If the cleaning work in this step is not in place, in the subsequent oxidation process will lead to the oxidized film is not easy to color, or coloring is not uniform enough, so that the phenomenon of yellowing.