Why charged powder clings to a metal part
Inside an electrostatic spray gun, dry coating particles pick up an electrical charge. The metal part is connected to ground, giving excess electrical charge a path away. As charged powder approaches, the metal’s electrical field pulls it toward the surface; the grounded part also lets charge drain away when particles land. The powder stays in place long enough to move the part to an oven.
Grounding matters because it helps create the electrical attraction and reduces the risk of stray charge building up on the workpiece. It does not mean the part is a magnet: the pull comes from electric charge, not magnetism.
The oven turns loose particles into a continuous coat
The deposited layer is still dry and fragile. In the oven, heat softens the polymer particles until they melt together and flow across the surface, filling small gaps between grains. Depending on the powder’s formulation, further heating can also trigger a chemical cure that links the polymer into a tougher, more durable coating.
That sequence—charge, deposit, melt, and cure—lets manufacturers apply a finished-looking layer without first dissolving the coating in liquid solvent. Unused powder can often be collected and reused, while the oven converts the powder left on the part into a smooth shell.
