| Early use of iron
Iron ore was
known from very early time and long before development of it. The technology
of smelting was known in the Hittites in Anatolia, or Asia Minor, and that
was about 1400 BC.
The Hittites not only developed iron smelting, but for many years they
controlled the area's supply of iron ore. Because of its hardness the Hittites helped change the tools of agriculture and
|Smelting and Cementation|
China and India were probably the first nation knowing the technology of smelting iron from ore and then spread westward. Cementation was discovered about 1400 BC the Chalybes, a subject tribe of the Hittites. They invented a cementation process to make iron stronger. The iron was hammered and heated in contact with charcoal which made the iron hard.
the end of Hittites empire the knowledge of smelting and cementation
gradually spread to Syria, Egypt, and Macedonia, also the Hittites
scattered and carried the knowledge of ironmaking to other peoples.
Widespread use of iron for weapons and tools began about 1000 BC. This was
the start of the Iron Age. The
ancient Egyptians increased smelting temperature in the furnace by new
technology of blowpipes and bellows.
The Greek by quenching the hot metal in cold water made hard iron weapons for soldiers of about 500 BC . Afterwards, the Romans tempered iron by reheating it after quenching. Indian literatures contains accounts that the ancient Hindus used iron. It seems that iron was the child of Hittites whose raised up by all old nations.
Thanks to God that we are in the present time so we do not need to harden the iron by our hands.
|Development Methods of Ironmaking|
Iron is not not found pure in nature, it contains waste rock from which it must be separated. In order to heat the iron, old iromaking peoples made a "furnace" which was a shallow pit dug in the ground.
Ore was placed in the bottom and a charcoal fire started on top. As the burning progressed, blasts of air were blown through nozzles in the sides of the furnace. This was done with bellows made from the skin of goats or other animals. The result of this process was the sponge iron.
iron was then broken into smaller pieces and by a hammer they beat out the
remaining waste then it was shaped. The ironmaker could also harden the metal by
cementation and tempering.
During the Middle Ages, the blacksmiths kept the old methods of smelting and cementation so they made chain mail and weapons for knights, nails and tools, iron plows and horseshoes were used later.
Romans developed a furnace with great technology compared to other nations which
called Stuckofen, it was made
larger and higher for better air draft. It was the forerunner of the modern
The ideas continued in the area of blasting strong stream of air to make the iron heated better and faster in the time from AD 1200 and 1350 waterwheels turned by fast-flowing streams came into use for ironmaking. The high temperature that developed melted the iron, which was then formed into pigs of cast iron.
Coal and Coke Take Over as Fuel From about AD 1500 iron makers gave more thought to coal as a fuel to replace charcoal. Increased warfare had created a demand for iron, and wood for charcoal was scarce.
Another improvement came in 1784, when Henry Cort, an English ironmaker, invented the puddling of molten pig iron. Cort's rolling mill, which was patented in 1783, could make iron bars about 15 times faster than the old hammer method. Earlier, about 1740, crucible cast steel was invented by Benjamin Huntsman, of England.
|THE STEEL AGE BEGINS|
From 1850 to 1865 great advances in iron and steel processing took place. The Steel Age began about 1860. Up to 1860 only two types of iron were made, brittle cast iron and soft wrought iron. Steel, which is both hard and strong, was made in only small quantities and was expensive.