Aluminum parts can be finished with liquid painting or powder coating. Although these two finishing processes provide a protective layer, each coating has its unique features, advantages, and limitations. These coatings contain pigments, additives, and resins.
The main difference is that liquid painting contains a solvent whereas powder coating uses dry powder. Other differences include texture, color matching, and application method.
What is Aluminum Liquid Painting?
Aluminum liquid painting is a surface finishing technique used to coat aluminum parts by spraying them with wet paint. The coating can be sprayed in a single or multiple layers depending on the reason for the coating and the type of paint used. Aluminum liquid painting provides excellent resistance to impact, wear, corrosion, and chemical attack.
Does Liquid Painting Look Like Powder Coating?
Liquid paint can look like a powder coat, particularly to a person who has no experience in surface finishing. Both powder coat and paint coat are available in satin, matte, and gloss finishes. This makes it difficult to differentiate these finishes with a glance. Although liquid painting and powder coating appear to be similar, some obvious signs help to distinguish them.
How to Identify Liquid Painting from Powder Coating
By examining the following characteristics, it is possible to determine whether an
aluminum part is liquid-painted or powder-coated. If you cannot tell, you can reach out to a reliable powder coating service provider for consultation. Experienced technicians or engineers can help identify whether your aluminum part has a liquid paint or powder coat.
Texture
Although powder coating and liquid painting help achieve a variety of finishes, they are best suited for different finishes. For instance, liquid painting is suitable for a high-gloss finish, whereas powder coating is perfect for a matte finish.
You should also note that powder coating has a more textured, rougher finish than wet paint. This does not mean you cannot achieve a smooth finish with powder coating.
Thickness
Powder coating results in a thicker coat than liquid painting. The powder coat layer ranges from 2 mm to 8 mm in thickness. On the other hand, the paint coat ranges from 0.5 mm to 1.5 mm. Powder coating allows you to determine the ideal thickness before application and it is possible to counter-check the coat’s final thickness. Therefore, if you want to achieve the right thickness for optimal performance and durability, powder coating is the right method.
If your aluminum part has a thicker coat, then it is probably coated with a powder coating. It is advisable to use a gauge to measure the thickness level. The measurements you get will help you determine the category your aluminum part’s surface falls under.
Color
Color does not provide a foolproof method to determine whether an aluminum part has undergone liquid painting or powder coating. However, it can give you a rough idea of whether the part is powder-coated or painted.
Although powder coating has many benefits to offer, it is still undergoing improvement. It is easier to create a unique or custom color with liquid painting than it is with powder coating.
It is possible to mix liquid paints to create new colors. However, mixing dry powders can result in a speckled pattern as opposed to an even color. This is because powders can only be colored when they are being produced. You cannot create a new color on-site – unless you are after a speckled appearance. Therefore, if you can spot speckled color, then the product has undergone powder coating.
Evenness of Application
Although powder coating is known to result in a grainy texture, it applies more evenly as compared to liquid painting. Since powder coating involves the application of charged particles, it helps achieve an even coat. It does not matter whether you are dealing with complex surfaces, with powder coating, it is possible to achieve a uniform finish. Paint can make some parts of the part look better than others. Also, it can drip, ripple, or bubble, resulting in an uneven thickness and finish.
Flexibility
Powder coating can withstand surfaces that slightly expand or contract. This means if you find cracking or chipping in some parts, then the part is likely to be painted. However, if the part is used in an application with extreme temperatures, without any signs of chipping or cracking, then there is a possibility it is powder-coated. Also, coatings on parts such as springs are usually powder-coated.
You should note that thermoset powder coatings applied in thick layers do crack. Manufacturers and surface finishing providers avoid this by making powder coatings in thin layers. Therefore, it is common to come across paint chipping or cracking before you get to thermoset powder coatings.
Liquid Painting Vs. Powder Coating – Which is Better?
The purpose of a protective finish on aluminum is to protect against environmental damage and corrosion. It can also be used to provide aesthetic features. However, if the protective layer can easily be damaged by chipping or scratching, it is of no use.
Powder coating offers improved performance as compared to painting. In addition, powder coats are more resistant to scratching, chipping, and wear. This is because of thermal bonds that are formed during the curing stage. Also, it results in thicker layers. You will therefore find powder coated parts suitable for outdoor and extreme applications.
The flexibility of powder coating explains why it is often chosen over liquid painting for parts used in the transport industry. Remember that these parts are usually subjected to constant vibrations and movements. Powder coat finishes are more resilient in such environments.
Although physical toughness, it is possible to achieve excellent color retention with powder coating. You should note that extended exposure to sunlight, heat, and moisture can break resins found in powder and paint coating. This is called chalking and makes pigment and resin pigments to be less adhesive.
In addition to powder coating being more durable than liquid painting, it is equally safer to apply and store. Liquid paints can be hazardous for many reasons. For instance, most liquid paints are flammable. This requires highly protected storage to avoid chemical fires. Since powder cots do not contain fluids, they cannot emit volatile organic compounds when exposed to extreme heat.
You will also find powder coating to be cheaper than liquid painting. This is because it has a better utilization rate. Dry powder can be recycled as opposed to liquid paint. It is estimated that overspray can result in considerable loss of paint. Since powder coating does not require highly trained manpower, it has lower labor costs associated with it.
Quality Liquid Painting Services with Sunrise Metal
Sunrise Metal offers quality aluminum liquid painting services supported by advanced technologies in surface finishing. Through this process, it is possible to enhance the appearance of your aluminum parts and increase their lifespan.
Experts at Sunrise Metal argue that by painting your aluminum machine parts, you can increase productivity. Aluminum like most metals can oxidize and corrode hence compromising the performance of the part.
Sunrise Metal is ISO 13485, ISO 9001 and IATF 16949 certified. Therefore, the quality of the parts you get is assured. Moreover, the company is REACH and ROHS compliant. All surface finishing services offered by the company meet the current industry standards in terms of performance, quality, and safety. If you are looking for quality liquid painting services, look no further.