Plating is a surface treatment process used where a thin layer of metal is applied to the surface of an object to make it stronger and resist corrosion. Two common plating methods are electroplating and electroless plating. Both are used to coat materials with metal, but they work in very different ways.
How They Work
Electroplating uses electricity to deposit metal onto a surface. The object being plated is connected to a battery or power source and placed in a solution containing metal ions. When the electric current flows, the metal ions move toward the object and stick to it, forming a thin layer of metal.
Electroless plating, by contrast, does not need electricity at all. Instead, a chemical reaction causes metal ions in the solution to deposit onto the surface. This process can happen on its own, as long as the right chemicals are present, and sometimes the surface is treated first to help the metal stick. In electroless nickel plating, like https://www.poeton.co.uk/surface-treatments/plating/electroless-nickel-plating/, a chemical reaction leaves a uniform layer of nickel onto the surface without using any external electricity.
Surface Requirements
Electroplating only works on surfaces that can conduct electricity, so plastics and other non-conductive materials must first be coated with something that conducts electricity. Electroless plating can coat almost anything.
Coating Quality
Electroplating often produces uneven coatings because the metal tends to build up more at edges and corners, where the electric current is strongest. Electroless plating, however, produces a more even and consistent layer because it relies on a chemical reaction rather than electricity.