Powder coating is the dry finishing process, where electrically charged power particles are sprayed onto the surface of a pre-treated object, such as aluminium. After application, the sprayed coating is cured under heat. It provides optical enhancements for objects which also protects and is long-lasting.
A rather lengthy process, it starts with the workpiece having residue such as dust, rust, scale, dirt and grease, removed. This is followed by the application of a cleaning agent such as ethanol or acetone, as these leave no residue on the surface after evaporation. The workpieces must be completely dry before the actual powder coating process begins.
Powder spray pistols are used to apply the powder coat. These may be manually operated or configured within an automated setup, within a spray booth and cabin. The pain is applied electrostatically, requiring the particles to be charged. This is usually achieved via a process of ionisation (corona application) or triboelectric (or electrokinetic) charging. The electrically charged powder cloud from the pistol adheres electrostatically to the work surface, forming a layer of powder coating.
The final stage is the curing and drying of the newly powder coating workpiece. This is completed in an oven at temperatures between 140-200°C for between 5 and 30 minutes (typically).
Powder coated aluminium produces a high quality finish which is resistant to impact from chemicals, moisture, ultraviolet rays and extreme weather conditions. It also has a reduced risk of scratching, chipping, corrosion, abrasions, fading or other wear issues.
With proper care and maintenance, powder coated aluminium will enjoy a long life span with a little reduction in its allure.
Generally speaking, a cleaning frequency of quarterly (i.e. once every three months) should prove sufficient and combat the accumulation of grime, dirt and other atmospheric pollutants. In locations where these pollutants may be more prevalent, such as industrial areas or in close proximity to the ocean, a more regular maintenance program with cleaning completed every month or second month, should be set.
To clean powder coated aluminium, first remove any loose surface deposits with a wet sponge. Next, take a soft brush (non-abrasive) and a diluted solution of mild detergent such as liquid dish washing detergent and warm water, and use it to remove more stubborn particles and deposits. Finally, thoroughly rinse with clean water.
It's important to never use solvents, which may cause irreversible damage to the colour and result in gloss loss within a truncated period of time. Solvents to be avoided include acetates, dulon thinners, Methyl Ethyl Ketone, Petrol products, along with any alcohol based cleaners or those with acidic or alkali ingredients. Even milder solvents such as White Spirits should be avoided.
