Sherardising or sherardizing is a method of galvanising also called vapour galvanising. It is named for its discoverer Sherard Cowper-Coles (1900), who also patented the process and some other similar processes. Zinc evaporates and diffuses into the metal target object forming Zn-Fe-phases by heating the object in an airtight container with zinc powder. The temperature that the container reaches normally does not exceed the melting point of zinc. Another method of sherardisation is to expose the intended objects to vapour from molten zinc using a reducing gas to prevent oxidation.
Sherardising is ideal for small parts and parts that require coating of inner surfaces, such as batches of small items. The original system was quite complicated and expensive; however, today there are new systems in use which are simple, cost effective, and use less or no preparatory chemicals, making them environmentally friendly.
More information on sherardising: BS EN 13811::2003 (this is the British/European Union standard).
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