Seven Custom Finishes For Bolstering Aluminum Extrusions

Custom aluminum extrusions are an ideal choice for your project owing to its versatility, ecological viability, and cost-effectiveness. Not only is it a ‘green’ alternative due to its recyclability, but it is also non-corrosive with high strength to weight ratio. Its ability to extrude into complex profiles (shapes) makes it an exciting option for designer applications. Once decided upon custom aluminum extrusions, one must decide upon the finishing options in order to enhance its appearance through high-performance coatings and improve corrosion resistance.

Let us look at the 7 different types of finishes for your aluminum extrusions:

1. Mechanical Finishes– Available in a variety of textures, mechanical finishes are achieved through mechanical methods like polishing, sanding, buffing, blasting or grinding. They greatly enhance surface quality and can be used as a final finish or prepare the aluminum for other high-performance cosmetic finishes.

2. Chemical Finishes – They include etching and bright-dipping. While etching gives a highly frosted surface appearance, bright-dipping gives a glossy and shiny ‘mirror’ finish. Bright Dipping is a more popular option that is achieved by dipping the aluminum profile in a special dip-solution of nitric and hot phosphoric acid. Anodizing is often recommended after bright dipping to thicken the corrosion-resistant oxide layer along with a choice of a wide range of colors.

3. Pre-treatment – Includes coating the aluminum profile for greater corrosion resistance and to enhance paint or powder adhesion for subsequent finishing. While Chrome Conversion Coating Pre-treatment was popular earlier, sustainable and eco-friendly Chrome Free Pre-treatments are more in demand today.

4. Liquid Coatings – They comprise a variety of paints such as acrylics, polyesters and fluoropolymers. These paints generally contain Volatile Organic Compounds (VOCs), which evaporate during the baking or curing process leaving behind a film of volume solids on the extrusion. These coatings provide a uniform surface thickness and come in an impressive array of beautiful colors.

5. Anodizing – Is an electrochemical process that provides aluminum profiles with extra protection in addition to the natural oxide film. All aluminum alloys can be anodized to form a durable anodic oxide layer on the aluminum surface while retaining its metallic luster. It can also accept a host of vibrant colors to enhance the final finish of your extrusion.

6. Sublimation – Aluminumprofiles can go through a sublimation process for a variety of textured finishes. Post the base coat application of powder; technicians wrap the profiles with a patterned film. The subsequent sublimation process transfers the desired pattern directly onto the aluminum extrusions.

7. Powder Coating – Powder coatings provide a solid, durable finish, which can meet the most stringent performance criteria. The powder coating is applied as a solid on the aluminum profile and the solid particles fuse together to leave behind a film during the baking/curing process. With the industry moving towards environmentally sustainable products, powder coatings are gaining ground, as they do not contain solvents or VOCs. Thus, they can meet the new environmental regulations on the use of VOCs and solvents.

From electronics to consumer durables, transportation to construction custom aluminum extrusions are a vital component of your project. The choice of an appropriate finish will ensure that your aluminum extrusions are not only corrosion resistant but also aesthetically appealing!