In order to overcome the defects of surface hardness and wear resistance of aluminum alloy, expand the application scope and extend the service life,
Surface treatment technology has become an indispensable link in the use of aluminum alloy, and anodic oxidation technology is the most widely used
And the most successful.
The principle of Anodic oxidation of so-called Anodized aluminum tube is an electrolytic oxidation process in which the surfaces of aluminum and aluminum alloys are usually converted
It is an oxide film with protective, decorative and other functional properties.From this
The anodic oxidation of aluminum is defined to include only the process of forming anodic oxidation film.
The metal or alloy parts are used as anodes and their surfaces are formed into oxide films by electrolysis.Metal oxygen
Compounds change the surface state and properties, such as surface coloring, improve corrosion resistance, wear resistance and hardness,
Protect metal surface, etc.For example, anodizing aluminum by placing aluminum and its alloys in appropriate electrolytes (e.g., sulfuric acid, chromic acid,
Oxalic acid, etc., is used as an anode for electrolysis under specific conditions and applied current.Anodic aluminum or its alloy
Oxidize, form alumina thin layer on the surface, its thickness is 5 ~ 30 micron, hard anodic oxidation film can reach 25 ~
150 microns.The anodized aluminum or its alloy improves its hardness and wear resistance up to 250 ~ 500 kg
Good heat resistance, hard anodized film melting point up to 2320K, excellent insulation,
The breakdown voltage is up to 2,000 V, enhancing corrosion resistance in =0.03NaCl for thousands of hours
Corrosion.Oxidation film thin layer has a large number of micro holes, can adsorb a variety of lubricants, suitable for the manufacture of engine cylinder or
Other wear resistant parts;Membrane microporous adsorption ability can be colored into various beautiful and gorgeous colors.Nonferrous metals or their combinations
Gold (such as aluminum, magnesium and their alloys) can be anodized, which is widely used in mechanical parts,
Aircraft and automobile parts, precision instruments and radio equipment, household goods and building decoration.
Generally speaking, the anode USES aluminum or aluminum alloy as the anode, while the cathode selects the lead plate and places the aluminum and the lead plate together
In an aqueous solution, which contains sulfuric acid, oxalic acid, chromic acid, etc., electrolysis is carried out to form a surface of aluminum and lead plates
Oxide film.Of these acids, the most widespread is anodic oxidation with sulfuric acid.
Advantages of Anodized aluminum tube: protection, decoration, insulation, improve the binding force with organic coating, improve the binding force with inorganic coating
