Anodized Aluminum Plate VS Roll - Coated Aluminum Plate

1. Surface Treatment Process

Anodized Aluminum Plate

The anodizing process involves an electrochemical reaction. The aluminum plate is made the anode in an electrolytic cell, usually with an acid electrolyte such as sulfuric acid. During the process, a layer of aluminum oxide is formed on the surface of the aluminum plate. This oxide layer is integral to the metal surface and is highly adherent. For example, in a typical sulfuric acid anodizing process, the aluminum ions react with the oxygen ions in the electrolyte to form a porous aluminum oxide film. The thickness of this film can be controlled, typically ranging from a few micrometers to tens of micrometers.

The anodizing process can also be adjusted to produce different colors. It often uses dyeing techniques after the oxide layer is formed. The dye molecules penetrate into the pores of the oxide layer, and then a sealing process is carried out to lock the color, making the color more durable.

Roll - Coated Aluminum Plate

Roll - coating is a more mechanical - chemical process. The coating material, usually a polymer - based paint or a special coating compound, is applied to the surface of the aluminum plate through rollers. The aluminum plate passes through a series of rollers that evenly distribute the coating material. The coating thickness is usually relatively thin, generally in the range of a few microns to about 50 microns.

The coating materials used in roll - coating are diverse. They can include polyester coatings, fluorocarbon coatings, etc. These coatings provide different properties such as color, gloss, and corrosion resistance. For example, fluorocarbon coatings are known for their excellent weather resistance and can maintain good appearance and performance in outdoor environments for a long time.


  Anodized Aluminum Plate


    Roll - Coated Aluminum  Plate

2. Aesthetic Appearance

Anodized Aluminum Plate

The appearance of anodized aluminum plates has a natural metallic luster. The color produced by anodizing is often more matte compared to roll - coated plates. The anodized finish gives a sense of depth and texture because the oxide layer is an integral part of the metal surface. Colors achieved through anodizing can have a more subdued and elegant look. For example, an anodized silver - colored aluminum plate may have a slightly textured and understated shine that is different from the high - gloss look of some roll - coated finishes.

The anodized surface can also be customized to have different surface textures. Through different pre - treatment methods before anodizing or by using special anodizing techniques, textures such as brushed, sandblasted, or patterned can be created on the surface.

Roll - Coated Aluminum Plate

Roll - coated aluminum plates offer a wide range of color and gloss options. They can achieve high - gloss, semi - gloss, or matte finishes depending on the coating formulation and the application process. The colors can be very vivid and consistent. For example, a roll - coated aluminum plate with a bright red fluorocarbon coating can have a very eye - catching and uniform color across the entire surface.

The smoothness of the roll - coated surface can be adjusted during the coating process. A well - roll - coated plate can have a very smooth and even appearance, which is beneficial for applications where a sleek and flawless look is desired, such as in some modern architecture facades or high - end interior paneling.

3. Durability and Corrosion Resistance

Anodized Aluminum Plate

The anodized oxide layer provides good corrosion resistance. The aluminum oxide film acts as a barrier between the aluminum substrate and the external environment. It is resistant to many chemicals and is less likely to corrode under normal environmental conditions. For example, in a mildly acidic or alkaline environment, the anodized layer can effectively prevent the aluminum from being corroded. The durability of the anodized layer also depends on its thickness and quality. A thicker anodized layer generally offers better protection.

However, the anodized surface can be damaged by scratches or abrasions. Once the oxide layer is scratched through to the aluminum substrate, the corrosion resistance in the scratched area may be compromised. But in some cases, the anodized layer can self - heal to a certain extent. For example, in a humid environment, the aluminum oxide may re - form to some extent in the damaged area, providing a limited level of protection.

Roll - Coated Aluminum Plate

The corrosion resistance of roll - coated aluminum plates depends on the type of coating used. Fluorocarbon coatings, for example, offer excellent corrosion resistance and can withstand harsh outdoor conditions such as salt spray, acid rain, and UV radiation. Polyester coatings also provide good protection against corrosion but may not be as durable as fluorocarbon coatings in extreme environments.

The coating on roll - coated plates can also provide protection against physical damage to some extent. A well - adhered coating can prevent scratches and abrasions from reaching the aluminum substrate. However, if the coating is damaged, such as chipped or peeled, the aluminum underneath may be exposed and become vulnerable to corrosion.

4. Cost

Anodized Aluminum Plate

The cost of anodized aluminum plates can vary depending on factors such as the complexity of the anodizing process (including color and texture requirements) and the size of the order. Generally, the anodizing process may involve more complex equipment and chemical processes, which can lead to relatively higher production costs. However, for large - scale production, the cost per unit may be reduced through economies of scale.

The cost of anodizing also includes the cost of pre - treatment of the aluminum plate, such as cleaning and surface preparation, as well as the cost of the anodizing chemicals and energy consumption during the electrochemical process.

Roll - Coated Aluminum Plate

Roll - coated aluminum plates can have a wide range of costs. The cost is mainly affected by the type of coating material used. For example, fluorocarbon - coated aluminum plates are usually more expensive than polyester - coated ones due to the higher cost of fluorocarbon coatings. The roll - coating process is relatively more efficient in terms of production speed, which can also affect the overall cost. In general, roll - coating can be a cost - effective option for applications that do not require the unique properties of anodized surfaces and where a wide range of colors and finishes are needed.