Wet Processing

The processes of metal deposition and conversion via wet processing all require the part to be treated in a bath containing the material to be applied. They may require an electrical current to be applied, which is electroplating, or they may be due to a chemical reaction, which is electroless plating.


This is metal or alloy deposition obtained via an electric current in an electrolyte solution containing metal or alloy ions to deposit on a metallic base.
The part is connected to the negative terminal of a transformer.
The thickness of the deposit is in proportion to the electrical current intensity and duration of electrolysis.

Polished Nickel Bath Gold Plating Bath
Soluble Anodizing Non-soluble Anodizing

Electroless Plating

This is a deposit obtained using a suitable electrolyte solution containing metal ions for depositing and a smaller amount of metal to deposit (not requiring the use of electric current) either via:

♦ An electrochemical reaction, the deposit considered as displaced, the thickness is much less.
♦ A chemical reaction, the deposit is considered chemical and the thickness depends on the length of time.

Example of electroless nickel deposit:

Nickel sulfate + sodium hypophosphite + phosphorous nickel solution + ortho-phosphite + hydro-phosphite + sodium

♦ NiSO4 + NaH2PO2 + H2O NiP + NaHPO3 + H2 + H+ + Na2SO4

The nickel ions are reduced to a metallic form by the reducing agent which is the hypophosphite (it provides the activation).
A catalyst is a condition or component necessary for activation but it is not consumed or transformed by the reaction. It’s the temperature in our case.

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