Black Anodized Aluminum Surface Finish
Anodizing is an electrochemical process of altering the surface appearance and properties of metals. It toughens and thickness the protective oxide. In fact, the resulting finish is the second hardest to diamond. Black anodizing of aluminum helps protect against corrosion, resists scratching, and improves aesthetic properties.
Black Anodized Aluminum Process
Although the chemical anodizing procedure is the same for any given application, the methods vary depending on the physical shape and type of aluminum alloy used.
Continuous Coil Anodizing
The process involves the unwinding of the pre-rolled coils through anodizing, etching, and cleaning steps. This method is suitable for high volume foil, sheet, and products, such as space bars, reflectors, and roofing systems.
This process involves immersing aluminum parts in a line of treatment tanks. Cookware, castings, extrusions, and sheets are examples of items that can be batch anodized.
Advanced pre-treatment procedures can improve the quality and appearance of the end product. As a result, black anodized aluminum can look like stainless steel, polished brass, and pewter. The dielectric properties of the anodized finish provide a wide range of electrical applications.
The coating is estimated to be 30% thicker than the aluminum metal it replaces. That is because the amount of oxide produced is higher than the amount of aluminum metal replaced. You will find the black anodic coating to be porous to allow easy sealing and coloring.
There are different ways used for coloring anodized aluminum. These methods are electrolytic coloring, integral coloring, interference coloring, and organic dyeing.
In electrolytic coloring, the anodized aluminum metal gets immersed in a bath. The good thing about this process is that it provides color versatility and it is technically advanced.
When it comes to integral coloring, anodizing and coloring are combined into a one-step process. You should note that this process is more expensive than electrolytic coloring because it is power-intensive.
Benefits of Black Anodized Aluminum
When you compare black anodized aluminum to standard aluminum, there are noteworthy benefits.
Ease of Maintenance
Wear and scars from handling, installation, fabrication, and surface cleaning become non-existent. You only need to rinse or clean with water and mild soap to restore black anodized aluminum to its normal appearance. If there are tough deposits, you can use mild abrasive cleaners.
You should note that black anodized aluminum has improved corrosion resistance ability than regular aluminum. Although aluminum does not rust, it can corrode when you expose it to air, salt, moisture, and other corrosion-inhibiting chemicals. The good thing about anodized aluminum is that it is not likely to corrode due to the thick oxide layer.
You can dye black anodized aluminum to get a colorful aluminum part. Regular aluminum cannot be dyed. Therefore, if you are using regular aluminum, you are limited to its natural chrome appearance. By anodizing aluminum, you solve this problem.
Exposing it to chemicals, such as, sulfuric acid triggers the formation of an oxide layer and a porous surface. Thus, the porous surface can hold more dye than the non-porous, smooth surface of regular aluminum.
Although anodizing aluminum’s major benefit is to give it superior corrosion resistance, it also easy to lubricate. When you anodize aluminum, you create deeper pores, which allow retention of the lubricating film or oil. Remember that regular aluminum has a non-porous, smooth surface that cannot hold lubricating film or oil.
The truth is that anodized aluminum provides greater adhesion for primers and adhesives. That is because its oxide surface has deeper pores as compared to those of regular aluminum. Ideally, pores are holes in which liquids, primers, and adhesive flow when they are applied. Since black anodized aluminum soaks up liquids, it supports adhesion.
Aluminum anodizing provides a variety of color and gloss alternatives. Also, it eliminates or reduces color variations. When you compare anodizing to other finishes, you will find that anodizing ensures aluminum maintains the metallic appearance.
Health and Safety
You should note that aluminum anodizing is safe. That is because the anodized finish is stable, non-toxic, heat-resistant, and does not decompose. Anodizing procedure is a reinforcement process of a naturally-occurring oxide; it does not produce dangerous or harmful by-products.
As you know, the standard aluminum metal is an excellent conductor of electricity. However, its anodic coating is an excellent insulator. Thus, you can combine these two properties into systems and equipment that save energy. For instance, you can use the metal both for conductive and structural purposes, while the anodized part provides insulation.
Applications of Black Anodized Aluminum
Anodizing converts the standard aluminum metal into aluminum oxide. Thus, it creates a new product with a finish that is more weather-resistant and durable. Also, with the addition of an aesthetically pleasing appearance, it offers a wide range of possibilities. You will find black anodized aluminum used in industrial, consumer, and commercial applications.
Remember that black anodized aluminum cannot wear even under salt-water exposure or UV light. Also, it cannot fade, peel, or chip. Medical equipment and tools are some items that are made of anodized aluminum. These components and products are used in dental and medical equipment manufacturing, oxygen equipment, regulators, emergency room instruments, and lab apparatus.
Examples of Black Anodized Aluminum Products
Appliances – Dryers, microwave equipment, coffee brewers, dryers.
Food Industry – Cookware, grills, coolers, display cases, and pans.
Home and Office – storage desks, beds, tables, picture frames, clocks, and bathroom accessories
Sports and Leisure – Boats, golf carts, fishing, and camping equipment
Automotive – Motor vehicle components, such as nameplates, control panels, wheel covers, and trim parts.
Construction – Building exteriors, roofing systems, vents, patio overs, and curtain walls
Sunrise Metal Quality Control for Anodizing Aluminum
At all stages of anodizing aluminum, engineers and experts at Sunrise Metal monitor the process and product quality. Application of color and electrical power is pre-programmed.
Quality control is necessary to ensure there is uniformity to the end product. Some of the parameters that need to be uniform are density, film thickness, corrosion resistance, image clarity, sealing, and abrasion resistance.
Usually, the Sunrise Metal team uses Statistical Process Control (SPC) techniques to ensure they meet the quality assurance standards.