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What is diffusion Coating in Heat treatment of Steel ?

 Diffusion coating , or metallic cementation, is the process of  impregnating the surface of the steel with aluminum, chromium, silicon, boron, beryllium, and other elements.




Diffusion coating is accomplished by heating and holding steel parts in direct contact with one of the above elements which may be in the solid, liquid or gaseous state. This process imparts a number of valuable properties to steel, among which are high heat, corrosion and wear resistance. In many cases , steel subjected to diffusion coating may be used as a substitute for a high alloy steel. 

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