white iron
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White cast iron is a type of cast iron characterized by its high hardness and brittleness. This is because all of its carbon content exists in the form of cementite (Fe₃C), with no graphite present. This gives the fracture surface a bright, white appearance, hence its name.
Due to its extreme hardness, white iron cannot be machined and must be shaped by grinding. Its brittleness limits its applications, but it is sometimes used where high wear resistance is needed, such as in brake linings. A primary use of white iron is as a starting material for malleable cast irons, which undergo a heat treatment process to decompose the cementite into a more manageable form.12
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cast iron…either so-called gray iron or white iron, the colours shown by fracture. Gray iron contains more silicon and is less hard and more machinable than is white iron. Both are brittle, but a malleable cast iron produced by a prolonged heat treatment was developed in France in the 18th century,…
Read More…either so-called gray iron or white iron, the colours shown by fracture. Gray iron contains more silicon and is less hard and more machinable than is white iron. Both are brittle, but a malleable cast iron produced by a prolonged heat treatment was developed in France in the 18th century,…
Read More- iron processingWhite iron
White cast irons are usually made by limiting the silicon content to a maximum of 1.3 percent, so that no graphite is present and all of the carbon exists as cementite (Fe3C). The name white refers to the bright appearance of the fracture…
Read MoreWhite cast irons are usually made by limiting the silicon content to a maximum of 1.3 percent, so that no graphite is present and all of the carbon exists as cementite (Fe3C). The name white refers to the bright appearance of the fracture…
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