You can find powder coating almost anywhere today. It is used mostly as finishing for various types of metals and some forms of plastics. One of its most potent selling points is its durability. It is known to considerably resist corrosion and can be deceptively effective in protecting metal railings, fences, and others. Let’s try and look at the scientific process involved on how powder coating works.
Understanding Powder Coating
Basically, when we talk about powder coating, we are referring to a type of dry finishing process. This process is so popular that it is used in more than 15% of the entire industrial finishing market. Its continued popularity is attributed to the fact that it can be used on a wide range of products.
Powder coating was initially introduced about 40 years ago in North America. The process can be categorized either as thermoplastic or thermoset coating. With thermoplastic, the powder will not undergo any changes as it goes through the baking stage. In thermoset, the powder will react to the heat during baking allowing it to bond with other chemical elements resulting in a polymerized finish that is considerably tough.
Because of its toughness and beautiful finish, you can see powder coating being used as decorative and protective finishing. There are also numerous colors of powder to choose from making it easy to match any color scheme.
How it Works
Polymer resin systems are combined with pigments, flow modifiers, leveling agents, curatives, and other additives. During the powder coating process, these elements are melted, mixed, cooled, and grounded into uniform powder-like substance.
The material is then subjected to electrostatic spray deposition (ESD), a process that will allow the powder to coat and bind to metal. This is normally done with the use of a spray gun that will make the electrostatic charged powder particles to stick to the grounded metal portion.
After the parts are fully treated with powder coating, it will then go through a curing process. The heat from the oven makes the coating chemically react and produce long molecular chains with high cross-link density. The produced molecular chains will remain resistant to breakdown. This is the most common method of powder coating being used. Even non-metallic substrates can be treated with powder coating so you can use it on medium density fiberboard (MDF) and plastics.
There are instances where powder coating will be used during fluidized bed application. The preheated parts are initially dipped in hopper of fluidizing powder. This melts that coating, which then flows from the part. It is essentially to post cure based on the temperature and mass of the part as well as the type of powder being used.
Overall, powder coating process is seen as environment-friendly, cost effective, easy to do, and extremely durable.
Obviously, there is a great demand for powder coating for it to last more than 40 years. The growth can be attributed to the variety of outdoor materials that need to be powder coated. The process of powder coating has been extremely useful in protecting materials like snow blowers, frills, lawn mowers, and wheelbarrows among others. Powder coating makes it possible for these types of materials to combat harsh climates.
This is why it is not surprising that high market demand for powder coating services can be observed in industries like automotive, furniture making, consumer goods production, and architecture. In the automotive industry alone, countries like Germany, Brazil, Malaysia, and China make extensive use of powder coating for protecting and finishing car parts.
Add to this the production of motorcycles, which has found immense benefits in powder coating. With motorcycle parts almost completely exposed to the elements, durable and beautiful finish provided by powder coating helps motorcycles to continue functioning for a long time.
Now that you know how powder coating works, you need to know as well that not all service providers deliver the same high quality results.