The influence of other impurity components on the surface treatment of aluminum profile is also studied

Aluminum is the most common and harmful impurity in the iron, in the construction of industrial aluminum production process, when the iron content is more than 0.25% have not very normal tone, with the increase of iron content, gloss, tonal slant blue, light gray mantle was ugly.When low silicon content in gold, iron is more obvious, the effect of silicon on the high side when in a certain extent, reduce the harmful effects of iron, the iron and silicon to form AlFeSi intermetallic compounds, but also consume a part of the excess of silicon.Iron influence the formation of iron and aluminum is the main reason of the color or rod organization, from several microns to several microns, the electrode potential and aluminum is different, therefore affecting the oxidation coloring uniformity and continuity, also reduce oxide film gloss and transparency, affect the shading effect. 

A small amount of copper is beneficial to the mechanical properties and surface brightness of aluminum profiles without reducing corrosion resistance.But the oxide film is so dark that it can be seen by the naked eye. 

A small amount of manganese will eliminate the harmful effects of AlFeSi and reduce the production of extrusion lines.However, when the content of manganese is high, the oxide film is yellow, and as the content of manganese increases gradually, the color effect is worse. 

High zinc content, increased the difficulty of aluminum extrusion, profiles, coarse grains, mould loss is big, the oxide film is opacifying color, and lead to zinc ion in alkali corrosion fluid accumulation, zinc in the profiles on the horse, produce shining pear skin spots. 

When the titanium content is greater than 0.1%, it has a great influence on the color and color difference of aluminum profile, which is caused by the inhomogeneity of titanium. 

Therefore, from the protection of the surface quality of aluminum extrusions, the iron content should be less than 0.25% and other impurities should be less than 0.1%.