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How Nickel helps in making Iron ?

Nickel acts as a graphitizer but is only half as effective as silicon. Small amounts help to refine the sizes of grains and graphite flakes. Most additions are from 0.25 to 2.0 percent. Larger amounts from 14 to 38 percent are added in the grey Irons to resist heat and corrosion and have low expansivity. 






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