Electroplating: What is it and when is it used?

Electroplating is a process that has evolved greatly over the last 200 years since its invention in the early 1800s. It is a metal finishing (or metal improving) process for industrial applications.

How Does It Work?

Electric currents dissolve metal cations, which form a thin coating of metal on an electrode. This is electrodisposition, and the thin layer of metal is deposited onto the substrate or work surface.

The positive electrical terminal is connected to the anode, and the negative one is connected to the cathode (the piece of metal that needs plated). They are both submerged in an electrolyte solution, oxidizing the anode once a DC power supply is applied.

The solution contains metal atoms, which dissolve along with ions reducing at the cathode; this forms the coating. The rate of the anode dissolving needs to be equal to the rate of the cathode being plated. This is done by adjusting the electrical current running through the circuit.

Electroplating can be done to various metals. To improve the quality, you must prepare the right electrolyte. A single metallic element is normally used rather than an alloy, except for solder and brass, which can be electro-deposited. “Throwing power” means the plating is covered in an even fashion.

Applications

Many different sectors use the process of electroplating to cover one metal in a thin coating of another metal. The metal being used to coat the first metal’s surface tends to have a certain trait that the first metal does not, generally improving resistance to corrosion and wear.

Chromium plating is an example of electroplating. This can be seen on a huge range of products, such as bath taps, car parts, wheel rims, gas burners and many more. Further uses of electroplating include protection from surface abrasions, improving electrical conductivity, reducing friction, and preparing surfaces for painting or re-coating. Surface engineering specialists such as https://www.poeton.co.uk/ can help you with your electroplating needs.

Metals such as zinc, tin and copper are often used in electroplating, along with precious metals such as silver, palladium and gold. A single metal alone can be used for plating, but alloys (combinations of multiple metals) can also provide more value. For example, tin and silver are good finishes for surfaces that come into contact with strong electrical currents.