Powder coating provides a durable, high-quality finish for metal products. While it works well on both aluminum and steel, the process differs depending on the material you choose. Knowing the key differences between powder coating over aluminum and steel will enable you to tailor your techniques and application methods to the metal’s unique properties.
How To Prepare Each Metal for Powder Coating
Proper surface preparation is crucial for a lasting powder coat finish. You must sandblast steel to remove rust, mill scale, and other surface contaminants. Afterward, you will apply a phosphate conversion coating to enhance adhesion and provide extra corrosion resistance.
Aluminum, on the other hand, does not rust but can form an oxide layer that interferes with powder adhesion. To prepare aluminum, you must first degrease the surface to remove oils and dirt. Then, you will etch the surface with an acid solution before applying a chromate or non-chromate conversion coating to promote a strong bond.
Why Curing Temperatures and Times Vary
Curing is the process of baking the powder-coated part in an oven, which melts the powder into a uniform, durable film. Steel has high density and mass, so it requires more time and energy to reach the necessary curing temperature. It heats up slowly but retains heat well, which can be beneficial for a consistent cure.
Aluminum has a lower density and heats up much faster, allowing for shorter curing times and lower energy consumption. However, its rapid heat dissipation requires careful temperature control to avoid over- or under-curing, which can affect the finish’s quality and durability.
What To Consider When Choosing a Finish
There are key differences in finish between powder coatings over aluminum and steel. Steel’s strength makes it ideal for heavy-duty industrial applications, where the powder coat adds an essential layer of protection against corrosion and wear. Aluminum is lighter and naturally corrosion-resistant, making it a great choice for architectural and decorative items where weight and aesthetics are primary concerns.
Professional Finishing offers a custom powder coating service for projects requiring specific colors or textures. We can tailor the finish to meet your specifications for aluminum or steel. Contact us today for a quote on our professional powder coating services.