A number of processes are applied in metal finishing. This is usually done by metal parts manufacturing industries. This procedure is usually performed after a metal part has been formed by altering the surface of a workpiece using common metal finishes like pain, ceramic coatings, and other surface treatments.
Below are aimed to give you some ideas about the different processes involved in metal finishing:
Electroplating
This process is obtained by passing an electric current through a dissolved metal ions-containing solution and the object to be treated. The metal object serves as the cathode in an electrochemical cell which attracts ions from the solution. Metals like aluminum, brass, bronze, cadmium, copper, chromium, gold, iron, lead, nickel, platinum, silver, tin, and zinc are used in plating ferrous and non-ferrous metal.
The operations involved in metal plating are typically batch operations. Meaning to say, metal objects are submerged into a series of baths that contain various reagents for achieving the needed surface characteristics. Operators can either carry the workpieces on barrels or racks.
Electroless Plating
In electroless plating, the process involves chemical deposition of metal coating onto object using chemical reactions - different from the previous one which uses electricity. The basic component of electroless plating solution are a source metal (usually a salt), a reducer, a complexing agent to hold the metal in solution, and other chemicals purposely designed to main stability and increase the life of bath.
Immersion Plating
This process is similar to electroless plating as this uses a chemical reaction to apply the coating. The difference is that the reaction is caused not by mixing two chemicals into the plating, but rather by metal substrate. The procedure produces a thin metal deposit by chemical displacement, commonly zinc or silver.
Chemical and Electrochemical Conversion
This particular treatment gives protective and/or decorative coating on a metal surface. This includes processes like anodizing - an immersion process in which the workpiece is put in a solution (usually containing metal salts or acids) where a reaction occurs to form an insoluble metal oxide. The reaction continues and forms a thin, non-porous layer that protects object from corrosion.
Riza Deshpande is an Internet enthusiast who loves to share useful information on electronics and manufacturing industry-related topics. Specifically she wants to share online her knowledge on topics like metal plating and anodizing.
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