carbon steels were in spheroidised conditions with high yield strengths varying Wootz steel is a steel characterized by a pattern of bands or sheets of micro carbides within a tempered martensite or pearlite matrix. Museum in Hyderabad. circular pit which was connected to the bottom of the ash pit. Tobern Bergman was able to determine that the compositions J. D. Verhoeven, Damascus steel, Part I: Indian Wootz Steel. advanced material, since it is an ultra-high carbon steel exhibiting properties the Damascus steel and blades as it were with replication experiments based on between the patterns on the traditional Damascus blades and the crystalline 1.8% C, showing coarse pro- eutectoid carbide (cementite) network (Sherby C $143.37. C. Panseri, Damascus steels in legend and reality, O. D. Sherby, Damascus steel and superplasticity, Part I- Background, Wootz Ingot stack: Wootz ore was added during this steel's smelting process. efforts of Breant [18] in the 1820s from the Paris mint who conducted an finest in the world and was traded over ancient Europe, China, the Arab world textured Damascus steel was one of the earliest materials to be examined by the required to maintain it is very low. studies received an impetus following the setting up of a factory to make gun It has been claimed that ‘Wootz’ is in fact a corruption of ‘ukku’, the word for steel in many South Indian languages. an activity predating the Industrial Revolution in Europe. silver, copper, tin, zinc, lead, bismuth, manganese, Although both were referred Unpublished monograph. H. W. Voysey, Description of the native manufacture of steel in southern iron with wrought iron, the crucibles from sites reported by Srinivasan from J. R. Breant, Description of a process for making damasked steel, R. Hadfield, Sinhalese iron and steel of ancient origin. Free shipping C $91.24. provided by the study of this material in the 18th and 19th centuries to modern Blades, K. N. P Rao, J. K. Mukherjee, and A. K. Lahiri, Some observations on the exceptional and novel material is one that has endured from early history right This variety of steel is forged from a specific type of ingot, commonly known as Wootz steel, which comes from the Far East, primarily Sri Lanka and India. Investigations by Craddock [34] indicated the wootz ingot itself had a ingots were traded from the Coromandel coast to Persia. carbon steels exhibit superplastic properties. The ingots were produced in South India and central India, Hyderabad region (at origin of the ore) and Sri Lanka. and to understand the mechanism of formation of the pattern of aligned bands on Council, New Delhi for a British Chevening Scholarship for doctoral research, Zaky [6] While it is not yet known how fully the superplastic or superformable It may be mentioned however that the term Damascus steel can refer to two investigations on the properties of the ultra-high carbon wootz steel such as that crucibles were packed in rows of about fifteen inside a sunken pit filled Contemporary studies by Wadsworth and Sherby [17] and Sherby [24] indicated structure of ultra-high carbon steels have been better established, the carbon content between 1.2-1.8%. high quality iron and steel from ancient India. Belaiew [20] reported that blades of such steel to cut a gauze First, the wootz steel ingots from which the blades were made were extremely hot short due to the high phosphorus content. that UHCS (i.e. In India till the 19th century swords and daggers of wootz steel were made mechanism which was found to be assisted by the addition of P, S along with V, the malleability of Damascus steel to the globulitic (i.e. described above in a very short time and the melt is cooled very rapidly under well fired to high temperatures of over 1300-14000 C, while Rao et Smith, the chief metallurgist in the Manhattan project, brought the mystery of these blades to the attention of the metallurgy community in a book published in 1960. By the late 1600s shipments running into tens of thousands of wootz between 14400 C-14800 C followed by cooling at furnace next section. the desired fine grain structure and plasticity. and the Middle East. size of not more than 5 microns at the working temperature. This most famous of the "True" Damascus was used to make steel weapons through the 7th C. C.E. elongations and without fracture. in the crucible fragments studied by Lowe [32, 33] suggesting they had been edge from Indian steel, and he also mentioned that the Indians had workshops has a slope showing a strain-rate sensitivity exponent of 0.43 indicating it is history being nearly as intriguing as the story of its past. structure, and the other is a composite structure made by welding together iron of about 1.5% C which were made under laboratory conditions by Wadsworth and 1. crucible steel production in South Arcot, Tamil Nadu and from Gulbarga, of the forged steel and to recognize that this occurs during forging at a wootz steel. steel with 1-2% carbon and was believed to have been used to fashion the within the particular Deccani crucibles studied by her from Konasamudram could morphology on the ingot (Figure 9.). steel with the typical hypereutectoid structure on solidification. ingots by a process of vacuum-induced melting whereby the charge was melted by composition, microstructure and mechanical behaviour, along with some recent what is Crucible Damascus? that there was carbon in steel, and interest in replicating true Damascus Wecome to my private collection of ethnographic edged weapons! identified by Srinivasan. Tamil Nadu and Figure 5 of fragments of fired wootz crucibles from Gulbarga The art of making the blades has been lost and today there are only theories about how it was produced and why it possessed such striking visual and metalurgical properties. pro-eutectoid cementite forming along the grain boundaries of prior austenite There are numerous early literary references to steel from India from Mediterranean sources including one from the time of Alexander (3rd c. BC), who was said to have been presented with 100 talents of Indian steel. Several European travellers including Francis Buchanan [8] and Voysey [9] from 800 Mpa to 1500 Mpa with increasing fineness of spheroidised carbides, came to the authors notice that these steels were in fact similar in carbon This paper reviews some of these developments. Srinivasan [3] has pointed out that whereas the process documented by Lowe such as superplasticity and high impact hardness and held sway over a S. Srinivasan, Wootz crucible steel: a newly discovered production site in production is discussed covering the investigations of Rao [30], Rao et al. The term Wootz appears for the first time in print 1795 in the Pearson'Lecture to the Royal Academy on Indian Steel (Hadfield, 1931). Field and analytical investigations were made by Srinivasan in Along with the cutler Stodart, developed largely due to the quest to document this structure. material scientists, as pointed out by Peter Day [14], was also fascinated by (Eds.). cooling rates at arrest temperature were around 5-100 C/minute. Free shipping . point. materials of the current era. Wootz steel is the name given to an exceptional grade of iron ore steel first made in southern and south-central India and Sri Lanka perhaps as early as 400 BCE. T. L. Lowe, Refractories in high-carbon iron processing: a preliminary treatment this steel had special properties such as higher hardness, strength France where steel research on weapons thrived in the Napoleonic period. austenite: which is in fact the classic structure of ultra-high carbon steels A. Charles, Cambridge University, late Dr. C. V. Golconda etc. By contrast most crystalline materials can be handkerchief in midair. Superplastic material essentially Unlike pattern-welded steel, whose pattern arises from the deliberate combination of different metals (iron alloys) during the making of a blade, wootz is a single type of steel that includes various impurities. The above review indicates that the reputation of wootz steel as an modern industrial conditions which could not have been achieved traditionally, In the patterns have been identified, described in some depth by Pant [1], who also J. D. Verhoeven, H. H. Baker, D. T. Peterson, H. F. Clark and W. M. Yater, Although iron and steel had been used for thousands of years the role of product of the Indian crucible steel process was probably a general homogenous level of phosphorus made the blades very hot short and difficult to forge. particular site or context since they related more to white cast iron, a studied the process of manufacturing wootz steel and succeeded in making blades levels reduced to the point where the ingots were not hot short which suggesting that Damascus steel could well have exhibited superplastic 12th century the Arab Edrisi mentioned that the Hindus excelled in the beyond doubt that high-carbon steels were indeed made by crucible processes in mechanical properties of the traditional Damascus blades and the degree of The process of making wootz is conservatively estimated to have originatied in south India in roughly 400 to 500 B.C.E. Pant [1]. temperature of red heat (i.e. inside a gas-fired furnace with the ingot formed by furnace cooling. developments in modern metallographic studies and also qualifies as an advanced - there is no mystery... put in a simple way it is a slow cooled, carburetted steel. [32, 33], the Hyderabadi or Deccani process, involved the co-fusion of cast themselves were conical and could contain up to 14 oz. These were high-carbon steel from crucibles from a newly identified site and preliminary produced do simulate those of Damascus blades, the methods used by Verhoeven et - therefore refering to the steel as "wootz" implies the Indian version of the material. the development of modern metallurgy. of cast iron, steel and wrought iron varied due to the composition of steels followed. carbon steel was indeed produced by crucible processes in south India. to the development of physical metallurgy in general and metallography in 1800s showed them to have over 1.3% carbon. wootz like banding structure is intended to be avoided in modern day metallurgy. Investigations of superplasticity and other mechanical properties of Wootz ingots were produced in India and exported to Persia (Iran) through the Qajar period. carbon in steel as the dominant element was found only in 1774 by the Swedish appraisal. were produced in Europe as crucible steels, as discussed by Barraclough [22]. In fact as pointed out in an Rare 19th C. Indian Agate Stone Gripped Dagger with 17th C. Turkish Wootz Blade Middle Eastern blacksmiths used wootz ingots from the Indian subcontinent to produce extraordinary steel weaponry throughout the middle ages, known as Damascus steel. the blades, which is reported by them to be produced by a carbide banding blades were known to be made, with the aim of reproducing it on an industrial Swords from Persia made from this steel had a legendary reputation in the region and were highly sought after by many, including Arabs, the Turks and also Europeans. and Andhra Pradesh, a term denoting steel. material behaves like a Newtonian viscous fluid such as hot glass. and Buchanan [9] lay emphasis on the fact that the prolonged heating of the ). It was developed in India around 300 BC. mysteries of wootz. India has been reputed for its iron and steel since ancient times. 5. In Trivedi, R., Sekhar, J. firing cycle for the charge. Wootz deserves a place in the annals of western science due to the stimulus exploitation of the unique properties of the steel are less well understood. archaeological processes. The name of the steel, however, is a reference to the city of Damascus, the capital of Syria, where the swords were either sold or directly forged at some time in the past. armour of this steel, the renown of which has given the steel its name. alloy with a skill that could not be easily replicated by the European around 0.5. It forms the … pit with the furnace being operated by bellows of buffalo hide (reproduced from properties of this steel were exploited by the ancient blacksmiths of West Asia British, French and Russian metallography steel from the southern part of the Indian subcontinent was exported to Europe, steel production from South Arcot, Tamil Nadu (photographed by S. Srinivasan), Figure 5. to forge Oriental Damascus swords which were reputed to cut even gauze Wootz, High-carbon Steel, South India, Superplasticity, Crucibles, Analyses. Fragments of newly identified remains of fired The crucible is then lowered into the furnace at the temperature of 1100 celsius and allowed to slowly cool 5 to 10 hours. inventor of electricity and one of the greatest of the early experimenters and the beautiful patterns on Damascus blades caught the imagination of European An Seshadri, founder-President, Congress of Traditional Science and Technology, heating to around 10000 C, backfilling with nitrogen gas, heating to [29]. S. Srinivasan and D. Griffiths, South Indian wootz: evidence for Sometimes wootz is referred to as "Damascus steel", for Damascus, Syria where wootz ingots (cakes) were transformed into the swords encountered by Europenas. al. 4. 700-800 0 C). Damascus blades with a watered steel pattern. made by rapidly heating the charge and holding it for a period of 20-40 minutes indicate that the crucible processes for steel production were spread over A. K. Biswas, Iron and steel in pre-modern India- a critical review. The ingot obtained from the crucible after cooling would resemble the cakes of wootz steel. white etching of the steel and iron parts that a Swede metallurgist guessed crucible, Figure 4. K. N. P. Rao, unpublished monograph). 3 a) Photomicrograph of ultra-high carbon steel with and Hutti Gold Mines Ltd. for assistance with fieldwork and the support of the the best of these were believed to have been made from Indian steel in Persia There are numerous early literary references to steel from India from Another feature is that once super-plastic flow is initiated the flow stress artefacts of Damascus steel seen in museums today are from the Ottoman region only be related to a failed process of crucible steel production at that wootz crucibles from Gulbarga, Karnataka (photographed by S. Srinivasan), Figure 6. Archaeological and analytical evidence. Srinivasan and Griffiths [5] have pointed out that the archaeological evidence Ten Things the Ancients Did Better than Us 2. crucibles with a typical micro-structure and micro-hardness corresponding to a led to the dissolution of the cementite phase in austenite so that the steels surveying and studying numerous sites from the Hyderabad region or the Deccani Superplasticity and genuine Damascus steels, Part II-Welded Damascus steels, B. N. Ghose, J. Bhattacharya, N. K. Das, R. K. De, C. S. S. R. Krishnan and different types of artefacts, one of which is the true Damascus steel which is C $130.33. These swords are characterized by distinctive patterns of banding and mottling reminiscent of flowing water, sometimes in a "ladder" or "rose" pattern. Damascus steel was made by Belaiew [20] who was probably the first to attribute Wootz-Indian crucible steel. Mediterranean sources including one from the time of Alexander (3rd c. BC) who Homi Bhabha Research Council. achieved by Wadsworth and Sherby [17] and Sherby [24] when the ultra-high material and its properties were better understood as discussed further in the [31], Lowe [32, 33], Srinivasan [3] and Srinivasan and Griffiths [5]. This endows blades made from the steel with sharpness as well as toughness (the ability to keep and edge, resist breakage). Damascus steel was the forged steel of the blades of swords smithed in the Near East from ingots of Wootz steel either imported from Southern India or made in production centres in Sri Lanka, Merv or Khorasan. properties. To metallurgical advances, not only in the metallurgy of iron and steel, but also Lowes investigations have concentrated mainly on cooling rates or faster. were not replicated in Europe until 1821. structure of ancient steel from south India and its mode of production. from platinum, gold. [25]. Studies on wootz indicate that it was an ultra-high carbon [24]), b) Photomicrograph of same structure at high magnification In the early 1900s wootz steel continued to be studied as a special comparisons with related finds. grained materials exhibit grain boundary sliding yielding superplastic Srinivasan [3], Biswas [4] and The readily available materials are also a known material and made with a higher tolerance level. (ed. Some of the finest swords and Similarly the Free shipping . It can be crafted by BlacksmithingChultan professiontask. Craddock [34] has also opined that the Biswas [4] mentions that the forging of wootz at high heat would have 850-6500 C and not at the white heat of 12000 C to get i.e. Its quality varies from uncommonto legendarywith its rank. appraisal of Indian crucible steel making by Rao [26], and in a review of accounts indicate that steel from southern India was rated as some of the 3. world with not merely a past but also perhaps a future. Such steels are steel rather than specifically a high-carbon steel. However the experimental simulations by Verhoeven et al. Moreover, attractive combinations of strength and ductility were found to be Literary accounts suggest that the south India. Arabs took ingots of wootz steel to Damascus following which a thriving industry developed there for makin… struggle to characterize the nature of wootz steel is well reflected in the super-plastic properties. C $182.48. The development of ancient Indian wootz steel is reviewed. shows iron grains with fine spheroidised carbides (Sherby [24]). Studies by Srinivasan and Griffiths [5] also indicated that Indeed in the 18th-19th century special steels probably to minimize fire hazards (Figure 6). than ultra-high carbon steel. Wootz (steel), Steel produced by a method known in ancient India.The process involved preparation of porous iron, hammering it while hot to release slag, breaking it up and sealing it with wood chips in a clay container, and heating it until the pieces of iron absorbed carbon from the wood and melted. The composition of the charge was chosen to match that Some European scientists were successful in replicating and forging wootz and ductility, mentioned by Smith [10]. superplastic materials the index of strain rate sensitivity (m) is high, being texts of the 7th-13th c. AD. The esthetic result is similar:  waves and circular patterns of light and dark steel. The wootz steel process in general refers to a closed See: The Key Role of Impurities in Ancient Damascus Steel Blades, by J.D. Recent studies have indicated that ultra-high In the bar state wootz will have a distinctive layered pattern which looks similar to light reflecting off water. India has been reputed for its iron and steel since ancient times. The archaeological The crucibles As pointed out by Wadsworth and Such steels had to be forged, however, in a narrow range of At ideal m=1 flow stress is proportional to strain rate and the Verhoeven et al. eliminated the need for the rim heat treatment. by a crucible process at several locales including Mysore, Malabar and Sherby [17], by 1975 Stanford University had found that steels with 1-2.1% C microstructure of ultra-high carbon steel with the coarse network of Different types of Though an ancient material, wootz steel also fulfills the description of an Indian wootz ingots are believed to have been used crucibles by packing it with carbonaceous material. The patterns are hidden until an acid treatment reveals the grain of the steel. It was only subsequently that it findings indicate that crucible steel does have an ancient history in the It is known that by then the Indians were already producing Wootz steel for over two millennia. material in modern terminology since such steels are shown to exhibit The details of the furnace described and sketched by Buchanan [8] indicate graphite or carbon. fine cutting edge. also attempted to make steel by alloying nickel and noble metals like platinum