Electroplating, an electrochemical process of coating a part with a thin layer of some other material, is a common industrial task. It is generally carried out to change some surface characteristics of the plated part. Improvements in aesthetic or corrosion resistance are two common objectives. Jewelry is one of the most common applications for electroplating.
The parts to be plated along with pieces of plating materials are immersed in plating tanks that are filled with a chemical solution. A source of electric current is then connected to the part and plating material and current is applied. An electrical circuit is formed through the materials and the electrolytic solution. Molecules of the plating material, freed by the electric current, begin to accumulate and form chemical bonds to the surface of the part being plated.
Altering the thickness or degree of corrosion resistance of the part being plated is achieved by controlling different variables of the electroplating process. These changes are achieved on the molecular level. Key characteristics that are often addressed in the process are aesthetics and hardness.
Jewelry is the best example of this plating modification. Base metals which are less expensive and more easily shaped can be coated with precious metals such as gold or silver. These items normally bear markings indicating the type of plating material used such as 24 karat gold or sterling silver. Adding the appealing appearance of precious metal with relatively low expense is perhaps the most common of all applications for electroplating.
The surface hardness of a part or tool can be vitally important to its application. Cutting tools, used in machining processes, are regularly plated with high hardness materials to improve performance. Chrome can add the benefit of hardness values approaching that of a diamond.
The combination of electricity and chemistry in the electroplating process makes possible the addition of many valuable characteristics to materials. Future applications similar to this process are being developed in nanotechnological applications with promising results. Electroplating is yet another example of how science is improving the ability to manipulate materials to great benefit.