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BASIC ENGINEERING
MATERIAL ED8E 11 | | |
 Ferrous (plain carbon Steels)
From this selection of steels an engineer who requires a plain carbon steel which can be cold formed
into a
certain shape e.g. a car body panel, would select a low carbon steel, as this material has the desired
property
i.e. Ductility .
An engineer who requires a plain carbon steel which can be used to cut other metals, including steel,
e.g. a cold
chisel, would select a medium carbon steel as this can have the desired property of hardness.
Plain carbon steels are those alloys of iron and carbon which contain up to 1.7% carbon. However
in practice,
most ordinary steels also contain up to 1.0% manganese, which is left over from a de oxidation operation
carried out at the end of the steel making process. This excess manganese dissolves in the solid
steel, slightly
increasing its strength and hardness. Medium and high carbon steels can be hardened and tempered
(toughened) all steels can be softened (annealed). See the chart below for some uses of steels
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Composition of plain carbon steels
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Common Name
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% of Carbon
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Common uses
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Mild Steel (or low carbon steel)
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0.1 to 0.25
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General purpose, used
throughout engineering.
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Medium carbon steel
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0.25 to 0.7
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Hammers and bolts and high
stress components
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high Carbon steel (or tool steel)
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0.7 to 1.7
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Metal cutting and forming tools
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