Iron Metal Production Techniques from Ores to Manufacture Commercial Forms of Iron Products

Five prominent Iron ores are available in earth crust occupying about 4.5 percent of it. They are:

  • Red haematite (Fe2O3)
  • Brown Haematite or Limonite (2Fe2O3.3H2O): It contain about 69.4% iron
  • Magnetite (Fe3O4) : It has 72% iron
  • Spathic Ironore or Siderite (FeCO3)
  • Pyrites(FeS2)

These iron ores are filled with impurities which are other than iron metal. Main percentages of impurities are sulphur, arsenic and phosphorus; remaining impurities are silica, aluminium, calcium carbonate and magnesium carbonate they all separated at initial stages of ore treatments methods.

Commercial forms iron metal products obtained from iron ore:

  • Pig iron or cast iron
  • Wrought iron or malleable iron
  • Steel (mild steel, high carbon steel and medium carbon steel)
  • Alpha, gamma and delta iron
  • Ferro alloys: carbon steels, alloy steels and stainless steel.
  • Ferro compounds of manganese, molybdenum, silicon, titanium, tungsten, vanadium, nickel metal
  • Super alloy metals

Cast iron or pig iron manufacture steps:

  • Concentration or dressing of the ore
  • Roasting or calcinations
  • Smelting in blast furnace

Wrought iron production techniques:

  • By puddling furnace method

Steel manufacturing process:

  • Cementation process
  • Crucible process
  • Bessemer process
  • Linz Donwitz or L.D. process
  • Open hearth process
  • Electric furnace method
  • Duplex process

Some general properties of Iron metal:

  • Iron melting point is about 1539oC.
  • Boiling point = 2740 oC.
  • Specific gravity = 7.88 g/cc
  • Tensile strength = 35,000 to 40,000 pounds per sq inch.
  • Electrical conductivity = 100,000 micro ohms/cc at 25 oC
  • Impact strength =  3.2 foot / pound
Temperature oC Specific heat, calories/gram
100 0.12
500 0.16
770 0.32
900 18.5

 

Temperature oC Creep strength, lb/in2
300 17000
400 12000
600 2500