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+--- Thread: What should we pay attention to in oxidation treatment of aluminum alloy (/Thread-What-should-we-pay-attention-to-in-oxidation-treatment-of-aluminum-alloy)
What should we pay attention to in oxidation treatment of aluminum alloy - haomeialu - 12-12-2017
In real life, there is much anodic oxidation for aluminum alloy plate, and it can be used in daily life. The characteristics of this process make aluminum surface produce a hard protective layer, which can be used for the production of kitchen utensils and other daily necessities. But the casting of aluminum anodic oxidation effect is not good, the surface is not bright, and it is only black. And the anodic oxidation effect of aluminum alloy profiles is better.
Before the selection of oxidation process, aluminum or aluminum alloy to understand the situation, because the quality of the material quality, the different components, will directly affect the quality of aluminum products after anodizing. For example, if the surface of aluminum, such as bubbles, scratches, from the skin, rough and other defects, after anodizing, all flaws will still be revealed. The alloy composition, the anodic oxidation of the surface appearance, also have a direct impact.
For example, with 1 ~ 2% manganese alloy, after oxidation was brown blue, with the aluminum content of manganese increased, the surface color after oxidation from brown to dark brown conversion. Silicon containing 0.6 ~ 1.5% of the aluminum alloy, after oxidation was gray, containing silicon 3 to 6%, was white gray. Zinc containing milky color, chrome-containing golden to gray uneven tone, nickel-containing pale yellow. In general, only magnesium and titanium containing more than 5% of the aluminum content, embossed aluminum plate can be obtained after the colorless, transparent and bright, smooth appearance.
In the choice of aluminum and aluminum alloy material, naturally take into account the selection of a suitable anodizing process. At present, China's widely used sulfuric acid oxidation, oxalic acid oxidation and chromic acid oxidation.
RE: What should we pay attention to in oxidation treatment of aluminum alloy - aadaasdark8072 - 01-10-2019
Typically, in contact with the atmosphere, the aluminium surface is covered with an aluminium oxide layer, with a thickness of less than 1-2μm. Due to its low thickness, high porosity and low mechanical strength, this layer does not protect the metal from corrosion. Anodizing for protective and decorative purposes is the most common method of superficial oxidation processes and is carried out through anodic oxidation.
The oxide films, resulted from anodizing, are porous, have a thickness of 20-50μm, and are heat-resistant, stable to water vapour and other corrosion agents.
Hard anodizing complies with the same obtains principles as well as decorative and protective anodization. The difference is in that hard anodizing is achieved at low temperatures and high intensity of electric current.