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History:
TECHNOLOGY VIA THE THIRD
EYE-AKASHIC 3-D DATA BASE OF 17-BILLION YEARS
Wootz steel
originated in India.[1][2] There are several ancient Tamil, Greek, Chinese and Roman literary
references to high carbon Indian steel since the time of Alexander's India campaign. The crucible
steel production process started in the 6th century BC,[citation needed] at production sites of Kodumanal in Tamil Nadu, Golconda in Telangana, Karnataka and Sri Lanka and exported globally; the Tamils of the Chera Dynasty producing what was termed the finest steel
in the world, i.e. Seric Iron to the Romans, Egyptians, Chinese and Arabs by 500
BC.[3][4][5] The steel was exported as cakes of steely iron that came to be known
as "Wootz."[6]
The Tamilakam method was to heat black magnetite ore in the presence of carbon in a
sealed clay crucible inside a charcoal furnace. An alternative was to smelt
the ore first to give wrought iron, then heated and hammered to be rid of
slag. The carbon source was bamboo and leaves from plants such as Avārai.[6][7] The Chinese and locals in Sri Lanka adopted the production methods of
creating wootz steel from the Chera Tamils by the 5th century BC.[8][9] In Sri Lanka, this early steel-making method employed a unique wind
furnace, driven by the monsoon winds. Production sites from antiquity have
emerged, in places such as Anuradhapura, Tissamaharama and Samanalawewa, as
well as imported artifacts of ancient iron and steel from Kodumanal. A 200 BC Tamil trade guild in Tissamaharama,
in the South East of Sri Lanka, brought with them some of the oldest iron and
steel artifacts and production processes to the island from the classical period.[10][11][12][13] The Arabs introduced the South Indian/Sri Lankan wootz steel to Damascus,
where an industry developed for making weapons of this steel. The 12th
century Arab traveler Edrisi mentioned the "Hinduwani" or Indian steel as the best in the
world.[1]
Another sign of
its reputation is seen in a Persian phrase – to give an "Indian
answer", meaning "a cut with an Indian sword."[14] Wootz steel was widely exported and traded throughout ancient Europe and the Arab world, and
became particularly famous in the Middle East.[14]
Development of modern metallurgy.
From the 17th
century onwards, several European travelers observed the steel manufacturing
in South India, at Mysore, Malabar and Golconda. The word
"wootz" appears to have originated as a mistranscription of wook, an anglicised version of ukku, the word for
steel in the Kannada language[15][16] and Telugu Language.
According to one theory, the word ukku is based on the meaning "melt, dissolve"; other Dravidian languages have
similar-sounding words for steel. The Tamil language root word for the alloy is urukku.[17] Another theory says that the word is a variation of uchcha or ucha ("superior").
When Benjamin Heyne inspected the Indian steel in Ceded Districts and other Kannada-speaking areas, he was informed that the steel was ucha kabbina ("superior
iron"), also known as ukku tundu in Mysore.[18][19]
Legends of wootz
steel and Damascus swords aroused the curiosity of the European scientific
community from the 17th to the 19th century. The use of high-carbon alloys was not known in Europe previously and thus the research into wootz
steel played an important role in the development of modern English, French
and Russian metallurgy.[20]
In 1790, samples
of wootz steel were received by Sir Joseph Banks,
president of the British Royal society,
sent by Helenus Scott.
These samples were subjected to scientific examination and analysis by
several experts.[21][22][23]
Specimens of
daggers and other weapons were sent by the Rajahs of India to the International Exhibition of 1851 and 1862. Though the arms of the swords were
beautifully decorated and jeweled, they were most highly prized for the
quality of their steel. The swords of the Sikhs were said to bear bending and
crumpling, and yet be fine and sharp.[14]
Characteristics
Wootz is
characterized by a pattern caused by bands of clustered Fe
3C particles made of microsegregation of low levels of carbide-forming elements.[24] The presence of carbon nanotubes and cementite nanowires has been identified by Peter paufler of TU Dresden in the microstructure of wootz steel.[25] There is a possibility of an abundance of ultrahard metallic carbides in the steel matrix precipitating out in bands. Wootz swords, especially Damascus blades, were renowned for their sharpness and toughness.
Steel
manufactured in Kutch particularly enjoyed a widespread reputation, similar to those
manufactured at Glasgow and Sheffield.[14]
The techniques
for its making died out around 1700.[citation needed] According to Sir Richard Burton,[7] the British prohibited the trade in 1866:
About a pound weight of malleable iron, made from magnetic ore, is
placed, minutely broken and moistened, in a crucible of refractory clay,
together with finely chopped pieces of wood Cassia
auriculata. It is packed without flux. The open pots are then
covered with the green leaves of the Asclepias gigantea or the
Convolvulus lanifolius, and the tops are coated over with wet clay, which is
sun-dried to hardness. Charcoal will not do as a substitute for the green
twigs. Some two dozen of these cupels or crucibles are disposed archways at
the bottom of a furnace, whose blast is managed with bellows of bullock's
hide. The fuel is composed mostly of charcoal and of sun-dried brattis or
cow-chips. After two or three hours' smelting the cooled crucibles are broken
up, when the regulus appears in the shape and size of half an egg. According
to Tavernier, the best buttons from about Golconda were as large as a
halfpenny roll, and sufficed to make two Sword-blades. These "cops"
are converted into bars by exposure for several hours to a charcoal fire not
hot enough to melt them. They are then turned over before the blast, and thus
the too highly carburised steel is oxidised.
According to
Professor Oldham, "Wootz" is also worked in the Damudah Valley, at
Birbhum, Dyucha, Narayanpur, Damrah, and Goanpiir. In 1852 some thirty
furnaces at Dyucha reduced the ore to kachhd or pig-iron, small blooms from
Catalan forges; as many more converted it to steel, prepared in furnaces of
different kind. The work was done by different castes; the Muslims laboured
at the rude metal, the Hindu preferred the refining work. I have read that
anciently a large quantity of Wootz found its way westward via Peshawar.
When last
visiting (April 19, 1876) the Mahabaleshwar Hills near Bombay, I had the
pleasure to meet Mr. Joyner, C.E., and with his assistance made personal
inquiries into the process. The whole of the Sayhddri range (Western Ghats),
and especially the great-Might-of-Shiva mountains, had for many ages supplied
Persia with the best steel. Our Government, since 1866, forbade the industry,
as it threatened the highlands with disforesting. The ore was worked by the
Hill-tribes, of whom the principal are the Dhdnwars, Dravidians now speaking
Hindustani. Only the brickwork of their many raised furnaces remained. For
fuel they preferred the Jumbul-wood, and the Anjan or iron-wood. They packed
the iron and fourteen pounds of charcoal in layers and, after two hours of
bellows-working, the metal flowed into the forms. The Kurs' (bloom), five
inches in diameter by two and a half deep, was then beaten into tiles or
plates. The matrix resembled the Brazilian, a poor yellow-brown limonite
striping the mud-coloured clay; and actual testing disproved the common idea
that the "watering" of the surface is found in the metal. The
Jauhar, ("jewel" or ribboning) of the so-called Damascus blade was
produced artificially, mostly by drawing out the steel into thin ribbons
which were piled and welded by the hammer. Oral tradition in India maintains that a small piece of either white or black hematite (or old wootz) had to be included in each melt, and that a minimum of
these elements must be present in the steel for the proper segregation of the
micro carbides to take place.
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