What are the Steps of the Aluminum Anodizing Process?
Metals and metalization are very important to the civilization of humans. And aluminum plays a very crucial part in it. It is used in so many industrial applications with its specific features. So today, we need more durable and different colors of aluminum. As it is not possible to find them from nature in the way we desire, we need special processes to achieve this purpose.
Aluminum anodizing is a very common process in order to make the surface of aluminum more proper for industrial use. It is a coating method of aluminum in order to create a better surface. Also, it is a permanent method for coloring. So, what is aluminum anodizing? What are the important issues in this process? And what are the steps of aluminum anodizing? Now, we will discuss these.
What is the Definition of the Aluminum Anodizing Process?
Actually, we have already mentioned what aluminum anodizing is. But, for a more detailed explanation; Anodizing is using the electrolytic oxidation method for aluminum parts or aluminum profiles in order to make aluminum surfaces make a protective oxide cover. The most important feature of this coating is being resistant to abrasion or corrosion. This process will protect aluminum and increase its lifetime. The covering can be 0,1 to 1 micrometer thick, and generally transparent. Of course, it can be in different colors for coloring. You can check our other post about the anodizing process for more detailed information.
What are the Purposes of the Process
So why do we do this? Actually, it is for protection. Forming an aluminum oxide layer will make aluminum more durable and resistant. Abrasion and corrosion are the two effects that harm aluminum products. This way, we can protect them.
On the other hand, aesthetics is very important for industrial products. Different colors and shapes increase the popularity of them, help the designers to sell them. But simple paints or industrial dyes can’t be very effective for example on an aluminum U-profile. For a better and more persistent view, anodizing is very important.
What are the Steps of Aluminum Anodizing
Different types and purposes may require some different preparation or process in anodizing. But, we will consider the main process. No matter which type you will choose, the first step is preparation.
We can devide anodizing process into two;
- Mechanical (preparation ) process,
- Chemical (anodizing) process,
As anodizing creates a transparent coating, we should prepare the surface before the process. The mechanical process is applied in order to acquire a dull and shiny surface.
There are four different steps in the mechanical process.
In this process, the surface of the aluminum is polished by using some special equipment. A special kind of brush, which is produced by using some proper cloth, is used with again a special type of wax. But if there are so many scratches on the surface, another special brush is used for sandpapering.
This process is possible for both clearing scratches and also drawing some types of patterns on the surface.
Staining is a special process in order to prepare the surface for anodizing. But it is also a kind of cleaning or sandpapering process. This time, we again use a special type of stainless steel for the brush wire. The brush is used to shape the surface of the aluminum.
Clearing the Burr
This is the final step before anodizing. After these steps, we can begin the anodizing process.
As we mentioned before, anodizing is using aluminum as an anode in a special acid. In general, sulfuric acid is used for the anodizing process. Other types of solutions can be chromic acid, organic acid, phosphoric acid, or borate and tartrate.
The anodized layer occurs by passing a direct current through the electrolytic solutions we mentioned above, with the aluminum is used as an anode. During this process, hydrogen occurs at the cathode and oxygen at the anode creating aluminum oxide on its surface. Alternating or pulsed current is also possible but rare. And the voltage may change between 1 to 300 V DC, but generally, it ranges between 15 to 21 V.
Aluminum anodizing is a very important process to create more proper products for industrial desires. As Bor Aluminum Company, we manufacture the best quality of aluminum in Turkey. For more questions about aluminum anodizing and other related topics about aluminum, just contact us.
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