Electroplating is a process that uses electric current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode. The term is also used for electrical oxidation of anions onto a solid substrate, as in the formation silver chloride on silver wire to make silver/silver-chloride electrodes. The process used in electroplating is called electro deposition. It is analogous to a galvanic cell acting in reverse. The part to be plated is the cathode of the circuit. In one technique, the anode is made of the metal to be plated on the part. Electroplating changes the chemical, physical and mechanical properties of the work piece. An example of a chemical change is when nickel plating improves corrosion resistance. An example of a physical change is a change in the outward appearance. Copper plated areas of mild steel act as a mask if case hardening of such areas where it is not desired. Tin-plated steel is chromium plated to prevent dulling of the surface due to oxidation of tin.
Electroplating is widely used in various industries for coating metal objects with a thin layer of a different metal. The layer of metal deposited has some desired property, which the metal of the object lacks. For example chromium plating is done on many objects such as car parts, bath taps, kitchen gas burners, wheel rims and many others for the fact that chromium is very corrosion resistant, and thus prolongs the life of the parts. Electroplating has wide usage in industries. Some well-known examples are chrome-plating of steel parts on automobiles. Steel bumpers become more corrosion-resistant when they have been electroplated with first nickel and then chromium. Steel bolts last much longer because they are sold with a coating of zinc or cadmium that has been applied by electroplating. These electroplating and conversion coatings provide a double protection system for steel components. Virtually all types of steel can be protected including castings. Newly developed electrolytes and process methods are able to provide greatly increased corrosion prevention and brilliant finishes.
Purpose of electroplating:
· Appearance
· Protection
· Special surface properties
· Engineering or mechanical properties.
In India it is estimated that electroplating industry is now worth Rs. I000 crores (Rs. 10,000 million). This means that compounded average annual growth rate is about 16.6%.Indian chemical products are still the cheapest and of recognized quality. The export activity, which is now only 20 crores a year, can achieve 100% growth rate over the next ten years. The electroplating industry can acquire a size of Rs.2, 000 crores and can sustain this rate until 2015.
FURTHER INFORMATION:
The Complete Book on Electroplating & Allied Chemicals describes the detailed information on the subject. The major components of this book are- silver, gold, copper, complex salts of copper, silver and gold, chromium, zinc, hydrides of boron, acrylonitrile, phosphorus, indium, niobium and tantalum, titanium etc.
In order to get “The Complete Book on Electroplating & Allied Chemicals” please visit-
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