Essay On Cast Iron

Cast iron is an iron alloy with more than 2% carbon as the main alloying element. In addition to carbon, cast iron also contains from 1% to 3% silicon, along with varying amounts of manganese and also traces of impurities such as sulfur and phosphorus, which combine with carbon to give excellent cast ability. It tends to be brittle, hard and non-malleable, and its structure is crystalline and relatively brittle and weak in tension. It fractures under excessive tensile loading with little prior distortion. Cast iron is however very good in compression. It has much lower melting temperature than steel.

Steel and irons are both primarily iron with carbon as the main alloying element. Steel contains less than 2% and usually less than 1% of carbon, while all cast irons contain more than 2% carbon. The high carbon content

Pure iron rarely exists outside a laboratory. Iron is produced by reducing iron ore to pig iron through the use of a blast furnace. From pig iron many other types of iron and steel are produced by addition or deletion of carbon and alloys. It is a bright white metal that is malleable, ductile and is relatively soft metal. It also has a very high tensile strength and is a moderately good conductor to heat and electricity. Pure iron is relatively soft, but is significantly hardened and strengthened by impurities in particular carbon. Its surface is usually discoloured by corrosion forming red-brown oxides, since it combines quickly with oxygen of the air in the presence of moisture, but absolutely in dry air it does not rust.

The melting point of pure iron is 1,536 C and its boiling point is about 3000 C. Its density is about 7.87 grams per cubic centimetre. It is used more than any other metal for producing metal alloys. The most important iron alloy includes cast iron, pig iron wrought iron and steel. It is an excellent and versatile metal for construction and is cheap compare to