Metal plating is a method of plating where metals are deposited on the substrates. This process is used to coat and protect metals and other materials by forming a thin layer of metal over the substrates.
Metal plating can be done either by electroplating or an electroless plating process. Metal plating provides the following benefits to materials:
- Reduces chances of corrosion
- Provides aesthetic decoration
- Enhances solderability
- Increases strength
- Decreases friction
- Changes conductivity
- Increases paint adhesion
- Improves magnetism
Some common metal platings are:
- Chromium plating
- Gold plating
- Silver plating
- Nickel plating
- Copper plating
In metal plating methods, it creates an outer layer of gold, nickel, copper, chromium or other metal on the base metal to prevent corrosion or to improve the appearance of plated material. Plating can done almost all type of metal. The most common industrial plating metals are zinc, chrome and nickel. Following are metal plating stages:
- Cleaning and Surface Preparation of Metal:
- Oxide removal
- Alkaline cleaning
- Metal Plating (see below for descriptions):
- Electroless plating (autocatalytic)
- Immersion plating
- Finishing and Protection Treatments:
- Chromate conversion
Some common metal platings include:
- Chromium plating – it is primarily used for decorative purposes also protect corrosion and friction. Iron and steel commonly plated with chromium. It is done in chromic acid bath.
- Gold plating – commonly applied in the jewelry and electronics industry.
- Silver plating – very common in decorative and electrical industries. It has limitations; vulnerable to humidity and galvanic corrosion.
- Nickel plating – works on a variety of metals for decorative purposes, corrosion resistance and lowering friction. Nickel is normally bonded with copper and aluminum.
- Copper plating – this plating is very common for electronics components. It is normally used on low-cost metal.
- Rhodium plating, cadmium plating and tin plating are also kinds of metal plating used for both decorative purposes and corrosion resistance.