Anodized Aluminum Parts A Comprehensive Guide
We often use aluminum parts in many applications in our daily life. Specifically, we need anodized aluminum for corrosion resistance applications. The anodizing process is similar to an electrolysis process.
and dyes or pigments can offer you a wide spectrum of colors. The following 9 are the most important questions about anodized aluminum. Let’s learn more.
What Is Anodized Aluminum Parts?
As the name implies, aluminum, which is anodized through an electrochemical process, is called anodized aluminum. Anodized generally boasts some key properties. These are aesthetics, durability, corrosion, and wear resilience.
Because of these properties, anodized aluminum can be seen in diverse applications. Well, anodized is especially popular for its aesthetic appeal. You know, it can come with a wide range of color options & finishes.
Let’s find out some examples of anodized aluminum products. We are often familiar with various anodized aluminum parts. For instance, smartphone shells, laptop keyboards, and portable charge shells are noteworthy. In automotive vehicles, we often see anodized aluminum trim pieces, car door handles, exterior mirrors, car loudspeaker box parts, and more. Well, in architectural sectors, anodized finds applications such as window frames, curtain walls, panels, and more.
How Is Aluminum Anodized?
Anodized aluminum is an electromechanical process. Before the final oxidation process, there are several steps. These steps ensure the efficient oxidation of aluminum. However, the whole oxidation process involves two steps:
- Aluminum chemical oxidation.
- Aluminum anodizing coloring.
Subsequently, the aluminum chemical oxidation process involves five more steps.
Step 1 Chemical Degreasing: This process typically removes oils and contaminants from the aluminum surface.
Step 2 Washing: Using water, this step typically cleans the degreased aluminum part.
Step 3 Etching with acid light: Before going through the oxidation process, the metal parts undergo an etching process. Using an acidic solution, the metal parts are etched. This ensures a better anoding coating on the metal surface.
Step 4 Washing: Again, using water, these etched metal parts are cleaned.
Step 5 Oxidation: Finally, the oxidation process produces anodized aluminum parts. You can also say that this process takes place in an electrolyte bath. In most cases, the bathing solutions contain sulfuric acid. Now, like a typical electrolysis process, the aluminum part acts as the anode. On the other hand, another rod is used as the cathode. When the electric current is applied, the oxide layer forms on the surface of the aluminum. This stage is called an oxidation process. And, the layer is typically called aluminum oxide.
What Is The Primary Purpose For Anodizing Aluminum?
Anodized aluminum serves four main purposes. As a result, they are widely popular in various industries.
Purpose 1 Increase wear & corrosion resistance
Aluminum is a well-known material. They are strong & lightweight. You know, it is used for a variety of products ranging from electronic parts to car parts. Well, aluminum is more susceptible to corrosion. Therefore, anodizing aluminum is necessary.
Purpose 2 Aesthetic properties
Another great purpose of anodized aluminum is to provide extensive aesthetic properties. You can typically make any color on the surface of the aluminum. As a result, anodized aluminum is so prevalent in architecture, automotive, and consumer electronics manufacturing.
Purpose 3 Improved surface hardness
Anodized aluminum comes with an additional oxide layer. As a result, anodized offers improved surface hardness.
Purpose 4 Increased durability
Combining the above three purposes, we find that anodized aluminum also provides enhanced durability. The oxide layer also provides resistance to scratches and abrasions. Overall, anodized ensures a longer lifespan for the aluminum parts.
What Is The Difference Between Anodized And Raw Materials?
The raw material naturally comes with an untreated surface. Conversely, during the electrolysis process, anodized materials get an extra oxide layer.
What apart these two elements is their ability to resist corrosion. Well, raw aluminum is more susceptible to corrosion. Because of this, they are less durable than anodized aluminum. Conversely, anodized provides excellent corrosion resistance & strong surface layer. Therefore, they can offer more durability.
Can Materials Other Than Aluminum Be Anodized?
Yes, you can also anodize other metals except for aluminum parts. Some of them include magnesium, titanium, and stainless steel. But, aluminum is so far the most popular metal used in anodized metal parts.
Anodizing other materials may not yield the same result as with aluminum. In this case, material composition, conductivity, and the desired outcome typically influence the electrolysis process. Thus, they don’t offer similar results.
How To Make Color Anodizing?
You can obtain color anodizing using organic dyes, inorganic pigments, or a combination of both. During the electrolysis process, combining these dyes or pigments in the electric cell can make a wide spectrum of colors.
However, the color of the anodized aluminum or other metals may vary due to a few reasons. Common factors include the type of metal, anodizing process parameters, dying elements, varying surface finish, and environmental factors.
Why Is It Impossible to Anodize the Entire Aluminum Part?
You know, anodizing aluminum is a chemical bathing process. Here, the aluminum part acts as the anode. As a result, a hanger is utilized to keep this metal from sinking. Typically, the portion of metal attached to this hanger cannot be anodized during the electrolysis process. Therefore, it is nearly impossible to anodize the entire aluminum part.
Does Anodizing Aluminum Prevent Corrosion?
Yes, the main purpose of anodizing aluminum is to provide excellent corrosion resistance properties. Anodizing aluminum is highly corrosion-resistant due to its oxide layer on the metal’s surface. Raw aluminum is more susceptible to corrosion. Therefore, an anodizing process is applied to it to make it more accessible to diverse applications.
How Do You Keep Anodized Aluminum From Fading?
Before knowing how to keep anodized aluminum from fading, it is necessary to understand the factors affecting it. Two factors influence aluminum parts’ surface fading. These include aluminum alloy material and anodized film. Furthermore, the hardness of the oxide film might differ even between oxidation procedures on the same material. Of all the procedures, the hard anodizing procedure is the most obvious. However, anodized aluminum with coatings is often harder than raw aluminum. It should be noted that the raw aluminum has a hardness of HV100. The hardness of an aluminum part with a typical anodic oxide coating, on the other hand, is HV300. However, this hardness can reach up to HV500, the anodized film can reach 20-100um.
You must anodized to protect from UV exposure and harsh weather.
Conclusion
The 9 questions above give us a clear understanding of anodized aluminum. We hope these questions can help you make an informed decision while choosing the right anodized aluminum product. Especially in the case of color-anodized parts, people often make mistakes by choosing painted aluminum. Note that painted aluminum parts are susceptible to chipping, peeling, or scratching.
