What comes to mind when you see a silver fork in your home or at a fancy restaurant? Silver is such a beautiful color, so unique and eye-catching. The only problem is that it’s soft, not very sturdy, and easily bent with little force. If you had a damaged silver spoon, how would you return it to being shiny and new again? Fortunately, there’s a process called electroplating that can do just this!
This article covers the basics of what electroplating is, how electroplating protects metal objects from damage, and why some companies use electroplating as a protective metal coating.
What is Electroplating?
Electroplating is coating metal objects with an additional layer of metal, achieved by combining an electric current with a chemical solution.
At a basic level, think of the current as a flow of electrons passing through a piece of metal (an electrode). This electron flow causes metal ions to be pulled out of the solution and deposited on the electrode.
The metal dissolved in the solution used to create the electroplating coating is called the “electrode” or “anode.” The metal that is being plated out is called the “cathode.” The cathode is a piece of metal coated with the desired plating.
Here’s a four-minute video explaining the basics of electroplating.
How Does Electroplating Protect?
Electroplating is a chemical process that deposits a thin layer of dissolved metal (i.e., copper, nickel, gold, silver, etc.) onto the surface of an object, and electrons flow from an electrode into the solution. This process draws the metal ions out of the liquid and deposits them onto the object’s surface.
This deposition occurs because the plated object has a positive charge, while the solution and electrode have a negative charge. The positive charge on the object attracts the negatively charged ions and pulls them out of the liquid, depositing a thin layer of the desired metal onto the object.
The electroplated layer is extremely thin—less than a micron—and isn’t strong enough for use as a functional component. However, the layer protects an object from damage, though. For example, gold is a very soft metal easily dented or scratched. However, if electroplated with nickel, it becomes much more scratch-resistant.
Why is Electroplating Used as a Protective Coating?
As mentioned above, companies use electroplating as a protective coating for two main reasons: aesthetics and functionality. Electroplating enhances an object’s aesthetics by making it look more shiny, colorful, and eye-catching. It’s also used to protect the functionality of an object in the same way that painting a car protects the functionality: the coating protects the object from things like wear, corrosion, and scratches. The coating can also change the object’s functionality. For example, painting a door red makes it more visible, while painting it black makes it less visible.
How Can You Spot Electroplating?
You spot electroplated metal if you see the color of the metal in a different shade. For example, seeing a silver fork with gold coloring signifies gold plating. If you see wear and tear on a plated object, you can tell the passage of time removed the plating. For example, a silver fork with a black coating was probably originally electroplated with nickel. Over time, the nickel coating wears away, and the silver will show through.
The biggest drawback of electroplating is the coating isn’t as strong as the object underneath it. If you bend or dent the object, the coating breaks before the object underneath it does. The coating is also not very thick, so it wears away. Depending on the object’s base material, this happens within a couple of years.
Electroplating traces back over 200 years ago to the work of Luigi V. Brugnatelli, when the inventor linked a wire between a dissolved gold solution and a battery. Nearly 35 years later, his research became popular across Britain and Russia.
Advancements in technology and science led to an industry safely protecting a variety of metals, making it one of the ubiquitous finishes in the entire industry.