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CH1012
IRON & STEEL
To produce 1 kg Fe:
1.7 kg   hematite    0.5 kg coke
0.25 kg limestone  2.0 kg air
• Steel is an alloy, a material
with metallic properties resulting
from the combination of ³ 2 elements.
carbon steel   1.0% C  this is obtained in a basic oxygen furnace where oxygen burns off the residual impurities in the pig iron
  eg. Sabatier knives - soft, v. sharp, rust
• stainless steel 0.5% C, Mn, Cr, Ni
  eg. Opinel knives - hard, don’t rust
The Basic Oxygen Steelmaking (BOS) plant uses molten iron from the Blast Furnaces, cold scrap steel, and burnt fluxes (lime and dolomite) to produce steel.  Molten iron, at around 1350°C, and cold scrap are charged into the BOS Furnace. Fluxes are added and then oxygen is blown into the Furnace for around 16 minutes. This raises the temperature of the metal to around 1700°C and reduces the carbon content from around 4.5 percent to 0.05 percent, converting the iron to steel.