**2. Electrolytic coating**

In this method, a metallic protective layer is applied to a surface as a coating for the component typically carried out in aqueous solution. This process is supported by using an external voltage source generally called rectifier. On the other hand, for electroless deposition, a reduction medium is present in the electrolyte. The latter process is widely used for nonconducting materials' coating such as ceramics and plastics. The electrochemical method (electrocoating, electroplating) is used for deposition onto electrically conducting substrates.

Electrochemical deposition onto an object is achieved by putting a negative charge on it to be deposited and immersing into a solution which contains a salt of the metal. The metallic ions of the salt carry a positive charge are thus attracted to the object providing electrons to reduce the positively charged ions to metallic form when they reach the negatively charged object [1].
