Anodized finishes for aluminum have been available for almost 100 years. Some of the first recorded cases of the material being used are from the early 1920s. Back then, manufacturers added the finish to seaplanes to prevent the damaging effects of saltwater.
Why choose an anodized finish for aluminum?
While its thermal conductivity is lower than regular aluminum, anodized aluminum offers several advantages. Mainly, it offers superior protection over wear and tear. That’s important since CNC machining is an investment that you’ll want to keep in operation.
What Is Anodizing?
Anodizing is a technique that alters the exterior chemistry of metals as well as other materials. The substance protects metal from:
• General damage
Furthermore, the protection technique can improve the look of your equipment, giving your facility a clean, healthy appearance. Anodizing also increases the durability of your equipment.
If you were to compare anodized aluminum to standard aluminum, anodized comes out on top when it comes to resisting deterioration. While neither material develops rust, both may deteriorate if exposed to air, salt, moisture or other elements that cause deterioration. However, anodized aluminum is more resistant to corrosion due to its thick oxide coating.
How to Anodize Aluminum
To anodize aluminum, essential standard aluminum is dipped and treated in an electrolyte chemical bath. Once submerged, an electric current is activated to elicit the chemical reaction that causes a thick oxide layer to develop over the standard aluminum.
The anodizing aluminum cost is about $100 a load if you’re going with a clear covering. You can expect to pay around $50 more a load if you order the load in a color.
A major benefit of anodized aluminum is that you can get it in different colors. Anodized aluminum colors include lime green, red, purple and orange. It also comes in more neutral shades like pewter, black and gray as well as plain tones like clear or nickel.
How Is the Color Added?
Anodized aluminum is dyed so that companies can make colorful products from aluminum. You cannot colorize standard aluminum because the product doesn’t support it. During the anodizing process, the material is subjected to sulfuric acid, which is the acid that triggers the oxide layer. This layer is porous, which means that it holds dye well.
Once the dye is added to the exterior of the product, it fills in the empty pores created by the chemical reaction. The surface is then sealed to keep the color intact. This process makes anodized colors especially durable. You won’t be able to scratch them to remove the color because the dye sinks deep into the surface. In fact, the only way to remove the color is to grind it off the substrate.
Does Anodized Aluminum Offer Good Lubrication?
While anodized aluminum is known for its durability, the substance also has superior lubrication over standard aluminum. Since the anodizing process forms deep pores, they also allow for excellent oil or film retention. Standard aluminum features a smooth exterior, which means that it cannot hold onto any lubricating oil or film.
What Are the Adhesive Properties of Anodized Aluminum?
Anodized aluminum provides a good adhesive surface for glue and paint primer. Like many of the other benefits, the deep pores are the reason for this benefit as well. Basically, the pores are holes that hold adhesive, liquid and primer substances. Anodized aluminum absorbs these substances, resulting in better adhesion.
Is Anodized Aluminum Easy to Maintain?
Products like CNC machining are used frequently. This means that they’ll suffer from wear and tear. When your machining features an anodized surface, a basic rinse or a cleaning with mild soap and water will generally restore the exterior to a like-new condition. This makes maintenance easy. If your equipment needs a bit more elbow grease, you can use a mildly abrasive cleanser without damaging the surface of the product.
Is Anodizing Healthy and Safe for People?
Anodizing aluminum is a process that is safe for human health. When a finish is anodized, it makes the exterior chemically stable. The finish won’t decompose, and nor is it toxic. Anodized aluminum resists heat to the melting temperature of aluminum, which is 1,221 degrees Fahrenheit. When aluminum is anodized, it works to strengthen the natural oxide process.
How Does Anodized Aluminum Impact the Environment?
Because it’s recyclable, aluminum has a positive impact on the environment. According to the Aluminum Association, about 75% of the aluminum that has been produced is still being used today. Furthermore, the anodizing process is eco-friendly and cheaper than paint and powder coatings.
The anodizing process improves aluminum, extending the life of the metal. While substances like paint and plating generally prevent a product from being recycled, anodizing is a recycle-neutral process.
Aluminum conducts electricity, and anodizing provides insulation. Together, the two substances can be merged into systems that use fewer materials and save energy. Aluminum can be used as a structural or conductive component, and when it’s been anodized, the chemical process insulates the interior of the product and adds longevity to the structure.
When products feature anodized aluminum, the physical design can be simplified. It can also decrease the amount of space and wiring needed for a product.
Keep in mind that the anodizing process is water-based and requires no VOCs. Along with this, there are no solvents or resins used during the process. If pigmentation is used during anodizing, then extremely small amounts of it are needed. To anodize aluminum, processors do not use halogenated hydrocarbons or other toxic organics. In most cases, the process does not create any hazardous waste.
Weighing the Pros and Cons of Anodized Aluminum
Since anodized aluminum has a lower thermal conductivity, it may crack under temperatures of over 80 degrees Celsius. This makes it a bad option as a cooking surface. However, the benefits of anodized aluminum include increased product durability, aesthetic appeal and easy maintenance. At Gensun Precision Machining, we provide CNC milling and CNC turning services. We also provide a variety of finishing services to give your facility the look that you want. Contact us for more information today.