In the last article, we highlighted aluminum anodizing, which is a process that is both effective and common. Surface treatment technologies perform various functions with respect to product life and aesthetics. Powder coating is one of the most efficient and eco-friendly coating methods that is used on metal, wood, and plastic objects preventing corrosion, chipping, fading, etc.
In this article, we will explore the composition, pros and cons, maintenance, and practical uses of powder coating in detail.
What is Powder Coating?
What Goes Into Powder Coating?
Do you know what provides powder coating with resilience and a vibrant finish? It is a combination of four key components that work in unison like a well-oiled machine.
1. Binders
Each binder is made from either a polyester or epoxy resin. Because binders serve multiple purposes including protecting the surface from peeling easily, they help bind the ingredients together… at least until it is hardened into stone-like structure. Without them, the coating would peel faster than cheap nail polish.
2. Additives
Do you wish to protect that outdoor furniture from sun rays? Don’t worry, additives can do that. These powder protective additives go as far as to ward off heat, chemicals, and even the dreadful orange peel finish.
3. Pigments and dyes
Dyes help capture a color but are not limited to that purpose. Translucent effects (which are great for metallic finishes) can be dealt by dyes while blocking UV rays from surfaces is by pigments, which gives them the dual purpose title.
4. Fillers
Even though they may not be easy to spot or attractive, fillers like calcium carbonate or silica are essential. They are very useful for increasing thickness at a fairly low price, increasing protection from scratches, or even allowing a coating to bend without cracking.
Different Kinds Of Powder Coatings
The best known types of powder coating are epoxy, polyester, and fluoropolymer powder coatings.
Epoxy Powder Coatings
Epoxy powder coatings are widely used in industrial grade household appliances, electrical parts, and industrial equipment due to their excellent adhesion and chemical resistance. Its UV resistance however, is poor which makes it unsuitable for outdoor applications.
Polyester Powder Coatings
Polyester powder coatings do well in outdoor weather conditions and are commonly applied to automobile parts, fences, and structural buildings where they are exposed to the sun. Their effectiveness and resistance against fading makes these coatings desirable on outdoor surfaces.
Fluoropolymer Powder Coatings
These are used in high quality applications including aerospace, building facade, and marine use because of their ability to weather extremely well. This type of coating keeps its gloss and color, in addition to being able to withstand harsh surroundings.
Why does powder coating work?
The process of electrostatic attraction combined with heat curing is what allows powder coating to work on a variety of surfaces. The results are always long-lasting and even.
In the coating application stage, the powder gun renders an electrostatic charge to the coating particles using a specialized spray gun. The charge enables the powder to stick solidly to the surface that has been grounded, thus facilitating a high attractive force. This leads to an even coating on complex shapes and edges to minimize overspray and waste.
Once the powder is applied, the coated piece is placed in the curing oven. The heat applied causes the powder to melt and flow forming a uniform film. This process serves to chemically bond the coating making them stronger, more scratch-resistant, and more durable against corrosion.
Advantages and Disadvantages of Powder Coating
Advantages
• Strong Coatings: Surfaces coated with powder mechanically tend to resist shadings and scratches. In addition, these surfaces can withstand extreme moisture and temperatures.
• Sustaining Our Environment: This method of powder coating is considered a sustainable approach because it releases very low VOCs and is capable of recycling overspray.
• The Cost Is Right: The production cost is lowered because of less waste and quick curing times.
• Variety in Aesthetics: Coatings come in many varieties from glossy to matte and metallic to textured.
• Achieving A Uniform Thickness: The electrostatic method guarantees uniform thickness and consistent coverage on all surfaces, especially on CNC machined parts with complex geometries.
Disadvantages
• Financial Limitations: A totally automated powder coating line would incur overriding costs for the spray booths and curing ovens.
• Coating restrictions: Specific plastic and wood type substrates that do not have heat resistance capabilities will not be able to have a coating placed on them.
• Coating Restriction: Achieving ultra-thin coatings, less than 1 mil, is much harder than with liquid paint.
Maintaining Surfaces that Are Powder Coated
As we stated before, surfaces with powder coatings require little attention, but they can be maintained in pristine condition with a little more effort:
• Dusting: Use detergent or warm water with cloth while scrubbing to remove dirt. Scrubbing pads or harsh chemical cleaners should not be used.
• Scrutinize Occasionally: Paying attention to scratches or chips is essential. Touch ups while issues are small are a great deal before corrosion damage occurs.
• Control After Excess Moisture: Water is not much of a problem, but when it is left unmonitored, it can break down and damage a surface’s finish. This is why creating drainage areas where items that need to be outdoors should be placed is helpful.
• UV Protection: As for the external grade items or surfaces, the use of UV-stable powders is preferred as damage or direct sunlight can worsen the finishes.
Along with these, applying protective wax annually also yields good results. Following these steps would leave a coated product performing for years.
Uses of Powder Coating
Various CNC machined components are capable of having different kinds of powder coating done on them.
Automotive: It offers aesthetic and anti-corrosion advantages when employed in alloy wheels, the chassis, and engine components.
Construction: The pigmentation resists weathering, making it ideal for window frame, fence, and structural steel coating.
Consumer Goods: Appliances, bicycles, and garden furniture are greatly enhanced by powder coating due to its striking color and toughness.
Industrial Machinery: Protective powder coatings add value by shielding CNC machined components from intense mechanical, chemical, and abrasive wear.
Electronics: Enclosure and heat sink protection from environmental impact.
Conclusion
The surface treatment technologies offered by EASIAHOME are ideal for many CNC parts due to ease of anodization and powder coating.If your product needs powder coating treatment, you can contact our technicians to provide you with the best solution.
Frequently Asked Questions (FAQs)
Q: Why choose over liquid paint?
A: Eco-friendly, zero VOCs, thicker coatings, and higher durability.
Q: Is powder coating eco-friendly?
A: Yes – 95-98% of overspray can be recycled, it emits near-zero VOCs, and requires less energy than liquid coating systems.
Q: How durable is powder coating?
A: It resists chipping, scratching, UV fading, and corrosion better than conventional paints, often lasting 15-20 years outdoors.
Q: Can any material be powder-coated?
A: Primarily metals (aluminum, steel). Some plastics/wood can be coated using specialized low-temperature curing powders.
