If you’ve been wondering how long powder coating lasts or anything else relating to this matter, you’ve come to the right place. Today we’ll be covering powder coating in depth, including what it is, how long it lasts, and the benefits and drawbacks of such a coating.
What is powder coating?
Powder coating is a dry coating process used as a metal finish, mainly on industrial equipment, home appliances, automobiles and bicycle frames. It’s applied as a dry, free-flowing powder through an electrostatic process, then cured either under heat or with ultraviolet light.
Powder coating finishes are not only sturdy but flexible, which allows them to be extremely versatile as they can be used on different surfaces such as metal, concrete, steel and plastic, as well as used on both indoor and outdoor applications.
Powder coatings are frequently used for metal because they repel corrosive elements such as chemicals and water, thus offering excellent protection. They’re also known for being cost effective and high quality, providing both functionality and durability.
How long do powder coating finishes last?
The answer to this question depends on several factors. The longevity of the powder coating will depend on the quality of the preparation and application, the type of powder coating used, and the environment the powder is exposed to.
Powder coating finishes can last as long as 20 years, but regular use, UV exposure and outdoor elements may cause it to break down more quickly.
The type of coating used will also influence its lifespan – for example, coatings that have fluoropolymers and urethanes can last longer as they’re designed to withstand extreme conditions and are therefore often used on products designed for the outdoors.
On the other hand, epoxy coatings may hold up well indoors, but outdoors the coatings will decline at a much faster rate.
Generally speaking, powder coating finishes are extremely durable, and are able to stand up to adverse weather, physical impact, and wear and tear such as abrasions, scratches and chips.
Types of powder coatings
Powder coatings are either thermosets or thermoplastics, as these are the two main types.
Thermoplastic powder coating softens into a liquid when heated and is therefore both reversible and reusable. These types of coatings tend to be thicker and more durable than their thermoset counterparts, and for this reason, they’re often used on metal, auto parts, and larger appliances such as refrigerators.
Thermoset powder is different in the sense that it forms chemical bonds once cured, and this process makes it impossible to recycle. The chemical bonds mean that even in high heat this coating won’t melt away. It’s also a cheaper option compared to thermoplastic.
The powder coating process: how does it work?
How the powder coating is applied – and how well the surface is prepped for it – determines how well it adheres. There are various options for cleaning and prepping the surface. A degreaser and/or phosphate rinse is usually used, followed by a quick water rinse, then the powder is applied using a spray gun, and is then cured.
Powder coating consists of polymer resin combined with pigments, curative, flow modifiers, leveling agents, and several other additives. These elements are melted and mixed together, then cooled and ground into a powder. The preheating process allows an even finish, while cooling helps form a hard coating.
Powder coating differs from solvent-based paint in several ways. For one, there’s no overspray with the former, and while paint needs an adhesive to stick to a surface, powder coating needs an electric charge, which is where the electrostatic paint sprayer comes in.
This uses a positive electric charge to accelerate the powder towards the components.
The chemical bonding solidifies the powder coating, reinforcing it with strength and durability. Once solidified, more layers can be added to achieve the desired thickness and level of protection.
Advantages of powder coatings
Better for the environment: powder coatings contain no solvents and release little or no amount of volatile organic compounds (VOCs), which eliminates the need for costly pollution control equipment, and allows companies to comply more easily with the U.S. Environmental Protection Agency regulations.
They’re also far better for the environment, particularly thermoplastic coatings, as these are reusable and recyclable. The application process also creates minimal wastage, unlike paint, where overspray is difficult to avoid.
Better for you: as they release no solvents and very few VOCs, powder coatings are also safer to use, and even though wearing protective gear is still recommended, they’re far less of a health concern compared to other finishes.
More durable: powder coatings can produce much thicker coatings than conventional liquid coatings and won’t run or sag. They can last up to 20 years if applied correctly.
They look good: powder-coated items generally have fewer appearance inconsistencies and can also achieve a wide range of specialty effects that would be impossible to achieve with other coating processes.
The process is efficient: With powder coatings, the curing time is significantly faster compared to liquid coatings, especially when using ultraviolet light or advanced low-bake thermosetting powders.
Disadvantages of powder coatings
Less control over the coating: with powder coatings, it can be difficult to control how thick a coating gets. This can cause uneven levels of thickness, which affects the overall texture of the finish.
Getting colors right can be difficult: Even though recycling and reusing powder coatings is an advantage, it may also lead to cross-contamination. This means that the colors may not come out as intended, which also lowers efficiency and causes possible mismatched touch-ups. The easiest way to avoid this is to ensure the powders are packaged when not in use.
Powder coatings are economical, environmentally friendly, and best of all, they’re highly durable. With the right application, powder coatings could last up to 20 years, making them a highly cost-effective coating option.