Powder coating is a dry finishing process that has gained widespread popularity since entering the market in the 1960s, accounting for over 15% of the global industrial finishing market. The market continues to grow as companies turn to powder coatings for a high-quality, durable finish that is efficient to apply and environmentally friendly. An almost limitless choice of colours, textures, and advanced performance properties make powder the best option for both functional and decorative finishes.
Powder coatings are made of polymer resin systems, combined with additives to aid curing, add color, and enhance mechanical properties. The ingredients are combined, melted, cooled, and finally ground into a fine, uniform powder similar to icing sugar.
Unlike the liquid coating process, powder coating is a dry finishing process. During the powder coating process, dry powder is applied to a material's surface using electrostatic spray deposition, then heat cured and cooled.
There are three stages to this process: material preparation, coating application, and heat curing.
For most metal parts being powder coated, the coating material is applied via electrostatic spray deposition. This application method employs a powder spray booth, powder hopper, and electrostatic spray gun.
After the powder has been applied, coated materials are heated in an oven. Heat causes the powder to 'flow out'. In other words, the powder melts and gels together, forming ultra durable long-chain polymers with high cross-link density. These molecular chains are what give powder coatings their enhanced performance characteristics, as they are extremely durable and resistant to breaking down.