The use of aluminum profiles for finishing some areas of the house, as well as its use for interior design, has been going on for quite some time. The metal itself is characterized by high ductility, good appearance and light weight, but it oxidizes very quickly and becomes coated with a gray coating if it interacts with oxygen.
What is anodized aluminum?
In order to preserve the bright shine of metal products, I had to use a special coating. Due to the application of an additional coating, the appearance has not practically changed, but at the same time, such troubles as corrosion can be forgotten for a very long time.
In order to understand what anodized aluminum is, it is necessary to find out how the metal is coated with a protective film. Usually, metals are protected from the effects of the environment using various protectors and other things. In this case, the protective film is ordinary, but already oxidized aluminum, which has the chemical formula: Al 2 O 3 . However, it should be noted that in this case it will be presented not in the form of a soft and thin amorphous film, but in the form of a crystalline structure, which is very similar to spinel, for example.
What is characterized by the film?
It turns out that anodized aluminum is coated with a film of already oxidized material. This protective agent is characterized by the following properties:
- microcrystalline type structure;
- the base is presented in the form of a superdense film, and the outer layer is a film with a large number of pores;
- the adhesion of this oxidized composition to aluminum is very strong.
The last point is very important. It means that anodized aluminum will be able to maintain its protective layer under any load for 40 years or more. This greatly distinguishes this composition from such as a paintwork or nickel coating, which peels off of aluminum simply with time.
You can add that the result will depend on the selected technical layer. That is, the properties of the film may vary. It can be ultra-thin and make up only 10-25 microns in thickness of its structure. In this case, it can’t even be seen with the naked eye. However, even such a layer is able to protect the metal from any aggressive influences and at the same time transmit up to 95% of the light.
Anodizing technology
The uniform color of the anodized aluminum means that the finest protective layer is present on the material. The process of obtaining such a protective layer is based on the fact that anodic oxidation of aluminum occurs in the electrolyte solution. Depending on what kind of anodized aluminum you need to get at the end, three types of electrolytes are used:
- processing with a very low current in the presence of a constant voltage and a weakly acid type electrolyte;
- a coating of this type can be applied under the influence of a bichromatic acid electrolyte;
- oxidation of the substance can also occur in an alkaline type electrolyte.
In order to change the properties of the final film, it is possible to change parameters such as acidity, bath temperature, as well as the operating voltage at the anode and cathode.
Anodized aluminum cookware
It’s worth saying right away that only three types of technological process are used for the production of dishes: stamping, casting and forging. In the presence of aluminum with such a crystalline structure, all three types can be used. All manufacturers of kitchen appliances and utensils claim that the use of this material allows you to create a new generation of things. The main reason why it was impossible to use such a light and convenient metal earlier was the oxidation process. The moment of contact with food worsened their quality, and they could not be consumed. Anodizing solved this problem.
Aluminum sheet
In addition to dishes and other details, anodized aluminum sheets are also available. Besides the fact that this layer helps to get rid of corrosion, it also protects the metal from fading. Another property is increased wear resistance. Thanks to this, it was possible to improve the quality of all duralumin parts. This is very important in the manufacture of, for example, dashboards. The parameters of the sheets are as follows:
- sheet thickness is 0.5 - 2 mm;
- sheet dimensions - 500 × 600 mm;
- the minimum number of sheets in a batch is 1.
As for the use of anodized aluminum, immediately after its invention it was widely used for the production of aluminum (duralumin) parts for aircraft. Another application of this type of aluminum is as a protective layer for other elements, as well as the basis for applying paint. It is also worth adding that such a protective layer is much harder than aluminum itself. Due to this, the wear resistance of all elements is significantly increased. The protective sheath helps to make aluminum a good insulating material, but the possibility of local small breakdown is still present, and therefore this somewhat limits its use as an insulator.