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How does Silicon Helps in Cast Iron and Wrought Iron?

Silicon in cast iron may be present up to 2.5 percent. It promotes the formation of free graphite which makes the Iron soft and easily machinable. At the same time, this element Inhibits the pick - up of carbon during the melting of Iron. It also produces sound castings free from blow holes because of its high affinity for oxygen.

A very small amount of  silicon makes wrought Iron hard, brittle and unforgeable.








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