Powder coating consists of covering a metal part with a pigmented resin powder, then curing it in an oven. The powder is sprayed with a gun: electrically charged, it clings to the earthed part. During curing, at around 180 to 200 °C depending on the powder, it melts, flows and polymerises into a continuous, solvent-free film that is hard and impact-resistant.
The process applies to steel, galvanised steel and aluminium, after a pre-treatment that determines adhesion: degreasing, chemical conversion or blasting. It is not suitable for materials that cannot withstand the oven temperature. The choice of powder depends on use: epoxies are mostly used indoors, while polyesters resist UV better and suit outdoor use. Finishes range from matt to gloss, smooth or textured, in the full RAL colour range.
The film is thick, often 60 to 120 µm, and its thickness varies: it thins on sharp edges, builds up in internal corners and penetrates deep cavities poorly. It is therefore not a precision treatment: threads, bores, bearing surfaces and earthing points are masked, or designed with clearance. It is used for machine guards and covers, frames, metal furniture, railings, sheet metal and plate fabrication parts. Applied over a galvanised part, it forms what is known as a duplex system, more durable outdoors.
In a quote request
State the colour (RAL reference) and finish, the use (indoor, outdoor, aggressive environment) or the powder type required, the film thickness expected and the areas to mask. Specify the material, dimensions and weight of the parts, since the oven and hanging line have limits, as well as the hanging marks tolerated and their position. If salt spray resistance is required (NF EN ISO 9227), mention it. The guide on anodising, powder coating and galvanising helps you compare the options.