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70-455: The Ticknall Tramway was a 12.8 mi (20.6 km) long 4 ft 2 in ( 1,270 mm ) gauge horse-drawn plateway terminating at Ticknall , Derbyshire , England . It operated from 1802 to 1913. The industrial tramway connected the brickyards, lime quarries and lime yards of Ticknall to the Ashby Canal . It had branches to the quarries and lime works at Cloud Hill and to

140-449: A flux and give the material its unique, fibrous structure. The silicate filaments in the slag also protect the iron from corrosion and diminish the effect of fatigue caused by shock and vibration. Historically, a modest amount of wrought iron was refined into steel , which was used mainly to produce swords , cutlery , chisels , axes , and other edged tools, as well as springs and files. The demand for wrought iron reached its peak in

210-514: A bar, expelling slag in the process. During the Middle Ages , water-power was applied to the process, probably initially for powering bellows, and only later to hammers for forging the blooms. However, while it is certain that water-power was used, the details remain uncertain. That was the culmination of the direct process of ironmaking. It survived in Spain and southern France as Catalan Forges to

280-623: A bridge ( The Arch ) over the Main Street in Ticknall, which is still being used by farmers. It looks similar to canal bridges, is Grade II listed, as it is one of the oldest railway bridges in the world. Two 138-and-51-yard-long (126 and 47 m) cut and cover tunnels are well preserved in Calke Park. The longer tunnel is an underpass of the main drive to Calke Abbey, the hall of the Harpur family, which

350-582: A carbon content of less than 0.008 wt% . Bar iron is a generic term sometimes used to distinguish it from cast iron. It is the equivalent of an ingot of cast metal, in a convenient form for handling, storage, shipping and further working into a finished product. The bars were the usual product of the finery forge , but not necessarily made by that process: Wrought iron is a form of commercial iron containing less than 0.10% of carbon, less than 0.25% of impurities total of sulfur, phosphorus, silicon and manganese, and less than 2% slag by weight. Wrought iron

420-470: A final product. Sometimes European ironworks would skip the shingling process completely and roll the puddle balls. The only drawback to that is that the edges of the rough bars were not as well compressed. When the rough bar was reheated, the edges might separate and be lost into the furnace. The bloom was passed through rollers and to produce bars. The bars of wrought iron were of poor quality, called muck bars or puddle bars. To improve their quality,

490-463: A high silky luster and fibrous appearance. Wrought iron lacks the carbon content necessary for hardening through heat treatment , but in areas where steel was uncommon or unknown, tools were sometimes cold-worked (hence cold iron ) to harden them. An advantage of its low carbon content is its excellent weldability. Furthermore, sheet wrought iron cannot bend as much as steel sheet metal when cold worked. Wrought iron can be melted and cast; however,

560-533: A line using similarly flanged plates in 1788. A leading advocate of plate rails was Benjamin Outram , whose first line was from quarries at Crich to Bullbridge Wharf on the Cromford Canal . The early plates were prone to break, so different cross sections were employed, such as one with a second flange underneath. Some lines later introduced chairs to support the plates on the blocks, and wrought iron plates, increasing

630-434: A low scale to supply the steel to the artisan swordmakers. Osmond iron consisted of balls of wrought iron, produced by melting pig iron and catching the droplets on a staff, which was spun in front of a blast of air so as to expose as much of it as possible to the air and oxidise its carbon content. The resultant ball was often forged into bar iron in a hammer mill. In the 15th century, the blast furnace spread into what

700-449: A lower melting point than iron or steel. Cast and especially pig iron have excess slag which must be at least partially removed to produce quality wrought iron. At foundries it was common to blend scrap wrought iron with cast iron to improve the physical properties of castings. For several years after the introduction of Bessemer and open hearth steel, there were different opinions as to what differentiated iron from steel; some believed it

770-589: A number of patented processes for that, which are referred to today as potting and stamping . The earliest were developed by John Wood of Wednesbury and his brother Charles Wood of Low Mill at Egremont , patented in 1763. Another was developed for the Coalbrookdale Company by the Cranage brothers . Another important one was that of John Wright and Joseph Jesson of West Bromwich . A number of processes for making wrought iron without charcoal were devised as

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840-410: A process for manufacturing wrought iron quickly and economically. It involved taking molten steel from a Bessemer converter and pouring it into cooler liquid slag. The temperature of the steel is about 1500 °C and the liquid slag is maintained at approximately 1200 °C. The molten steel contains a large amount of dissolved gases so when the liquid steel hit the cooler surfaces of the liquid slag

910-410: A refinery where raw coal was used to remove silicon and convert carbon within the raw material, found in the form of graphite, to a combination with iron called cementite. In the fully developed process (of Hall), this metal was placed into the hearth of the puddling furnace where it was melted. The hearth was lined with oxidizing agents such as haematite and iron oxide. The mixture was subjected to

980-481: A single hearth for all stages. The introduction of coke for use in the blast furnace by Abraham Darby in 1709 (or perhaps others a little earlier) initially had little effect on wrought iron production. Only in the 1750s was coke pig iron used on any significant scale as the feedstock of finery forges. However, charcoal continued to be the fuel for the finery. From the late 1750s, ironmasters began to develop processes for making bar iron without charcoal. There were

1050-412: A strong current of air and stirred with long bars, called puddling bars or rabbles, through working doors. The air, the stirring, and the "boiling" action of the metal helped the oxidizing agents to oxidize the impurities and carbon out of the pig iron. As the impurities oxidize, they formed a molten slag or drifted off as gas, while the remaining iron solidified into spongy wrought iron that floated to

1120-477: A toll basis, with any rolling stock owner able to operate their wagons on the tracks. Sometimes, the plateway company was forbidden to operate its own wagons, so as to prevent a monopoly situation arising. Some plateways, such as the Gloucester and Cheltenham Railway, were single-track, with passing loops at frequent intervals. The single-track sections were arranged so that wagon drivers could see from one loop to

1190-424: Is redshort or hot short if it contains sulfur in excess quantity. It has sufficient tenacity when cold, but cracks when bent or finished at a red heat. Hot short iron was considered unmarketable. Cold short iron, also known as coldshear , colshire , contains excessive phosphorus. It is very brittle when cold and cracks if bent. It may, however, be worked at high temperature. Historically, coldshort iron

1260-413: Is mild steel , also called low-carbon steel. Neither wrought iron nor mild steel contain enough carbon to be hardened by heating and quenching. Wrought iron is highly refined, with a small amount of silicate slag forged out into fibers. It comprises around 99.4% iron by mass. The presence of slag can be beneficial for blacksmithing operations, such as forge welding, since the silicate inclusions act as

1330-414: Is a more important measure of the quality of wrought iron. In tensile testing, the best irons are able to undergo considerable elongation before failure. Higher tensile wrought iron is brittle. Because of the large number of boiler explosions on steamboats in the early 1800s, the U.S. Congress passed legislation in 1830 which approved funds for correcting the problem. The treasury awarded a $ 1500 contract to

1400-513: Is an archaic past participle of the verb "to work", and so "wrought iron" literally means "worked iron". Wrought iron is a general term for the commodity, but is also used more specifically for finished iron goods, as manufactured by a blacksmith . It was used in that narrower sense in British Customs records, such manufactured iron was subject to a higher rate of duty than what might be called "unwrought" iron. Cast iron , unlike wrought iron,

1470-435: Is brittle and cannot be worked either hot or cold. In the 17th, 18th, and 19th centuries, wrought iron went by a wide variety of terms according to its form, origin, or quality. While the bloomery process produced wrought iron directly from ore, cast iron or pig iron were the starting materials used in the finery forge and puddling furnace . Pig iron and cast iron have higher carbon content than wrought iron, but have

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1540-491: Is deceptive. Most of the manganese, sulfur, phosphorus, and silicon in the wrought iron are incorporated into the slag fibers, making wrought iron purer than plain carbon steel. Amongst its other properties, wrought iron becomes soft at red heat and can be easily forged and forge welded . It can be used to form temporary magnets , but it cannot be magnetized permanently, and is ductile , malleable , and tough . For most purposes, ductility rather than tensile strength

1610-407: Is no longer manufactured commercially. Wrought iron was originally produced by a variety of smelting processes, all described today as "bloomeries". Different forms of bloomery were used at different places and times. The bloomery was charged with charcoal and iron ore and then lit. Air was blown in through a tuyere to heat the bloomery to a temperature somewhat below the melting point of iron. In

1680-450: Is no longer produced on a commercial scale. Many products described as wrought iron, such as guard rails , garden furniture , and gates are made of mild steel. They are described as "wrought iron" only because they have been made to resemble objects which in the past were wrought (worked) by hand by a blacksmith (although many decorative iron objects, including fences and gates, were often cast rather than wrought). The word "wrought"

1750-615: Is now Belgium where it was improved. From there, it spread via the Pays de Bray on the boundary of Normandy and then to the Weald in England. With it, the finery forge spread. Those remelted the pig iron and (in effect) burnt out the carbon, producing a bloom, which was then forged into bar iron. If rod iron was required, a slitting mill was used. The finery process existed in two slightly different forms. In Great Britain, France, and parts of Sweden, only

1820-561: Is now owned by the National Trust . Stone sleeper blocks can still be seen at various points along the route. Benjamin Outram planned to use two horses to haul a train in the flat area, and support these by a third horse on the uphill section from Ticknall to the top of Pistern Hill. The support horse was to be led back by a boy four times a day, to support the uphill run of other trains. Consequently, four men, one boy and nine horses were required to transport 40 tons of stones from Ticknall to

1890-471: Is tough, malleable, ductile , corrosion resistant, and easily forge welded , but is more difficult to weld electrically. Before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. It was given the name wrought because it was hammered, rolled, or otherwise worked while hot enough to expel molten slag. The modern functional equivalent of wrought iron

1960-796: The Hay Railway , the Gloucester and Cheltenham Railway , the Surrey Iron Railway , the Derby Canal Railway , the Kilmarnock and Troon Railway , the Portreath Tramroad in Cornwall, and lines at Coalbrookdale , Shropshire . The plates of a plateway generally rested on stone blocks or sleepers , which served to spread the load over the ground, and to maintain the gauge (the distance between

2030-472: The Industrial Revolution began during the latter half of the 18th century. The most successful of those was puddling, using a puddling furnace (a variety of the reverberatory furnace ), which was invented by Henry Cort in 1784. It was later improved by others including Joseph Hall , who was the first to add iron oxide to the charge. In that type of furnace, the metal does not come into contact with

2100-546: The Surrey Iron Railway and the Kilmarnock and Troon Railway as plateways, though between these (in 1803) he designed the Ruabon Brook Tramway as using edge-rail. An alternative design, with the flange on the outside designed to be additionally used with flanged wheels, was unsuccessfully trialled on the Monmouthshire Canal Company's line shortly before its reconstruction as a modern railway. That idea

2170-595: The Walloon process was used. That employed two different hearths, a finery hearth for finishing the iron and a chafery hearth for reheating it in the course of drawing the bloom out into a bar. The finery always burnt charcoal, but the chafery could be fired with mineral coal , since its impurities would not harm the iron when it was in the solid state. On the other hand, the German process, used in Germany, Russia, and most of Sweden used

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2240-517: The bloomery ever being used in China. The fining process involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation . Wagner writes that in addition to the Han dynasty hearths believed to be fining hearths, there is also pictorial evidence of the fining hearth from a Shandong tomb mural dated 1st to 2nd century AD, as well as a hint of written evidence in

2310-413: The finery forge at least by the 2nd century BC, the earliest specimens of cast and pig iron fined into wrought iron and steel found at the early Han dynasty site at Tieshengguo. Pigott speculates that the finery forge existed in the previous Warring States period (403–221 BC), due to the fact that there are wrought iron items from China dating to that period and there is no documented evidence of

2380-778: The 1860s, being in high demand for ironclad warships and railway use. However, as properties such as brittleness of mild steel improved with better ferrous metallurgy and as steel became less costly to make thanks to the Bessemer process and the Siemens–Martin process , the use of wrought iron declined. Many items, before they came to be made of mild steel , were produced from wrought iron, including rivets , nails , wire , chains , rails , railway couplings , water and steam pipes , nuts , bolts , horseshoes , handrails , wagon tires, straps for timber roof trusses , and ornamental ironwork , among many other things. Wrought iron

2450-680: The 1960s, the price of steel production was dropping due to recycling, and even using the Aston process, wrought iron production was labor-intensive. It has been estimated that the production of wrought iron is approximately twice as expensive as that of low-carbon steel. In the United States, the last plant closed in 1969. The last in the world was the Atlas Forge of Thomas Walmsley and Sons in Bolton , Great Britain, which closed in 1973. Its 1860s-era equipment

2520-418: The 4th century AD Daoist text Taiping Jing . Wrought iron has been used for many centuries, and is the "iron" that is referred to throughout Western history. The other form of iron, cast iron , was in use in China since ancient times but was not introduced into Western Europe until the 15th century; even then, due to its brittleness, it could be used for only a limited number of purposes. Throughout much of

2590-572: The Ashby Canal, and on the return runs 12 tons coal, slack (coal dust) and other goods. 52°48′37″N 1°28′23″W  /  52.81015°N 1.47304°W  / 52.81015; -1.47304 Plateway Plateways consisted of L-shaped rails, where the flange on the rail guides the wheels, in contrast to edgeways , where flanges on the wheels guide them along the track. Plateways were originally horsedrawn but, later on, cable haulage and small locomotives were sometimes used. The plates of

2660-459: The Butterly Iron works, keeping them fully occupied for 15 months. The rails had each a length of 3 feet (910 mm) and an average weight of 38 lb (17 kg) were mounted onto setts (stone sleeper blocks) with a minimum weight of 150 lb (68 kg). Waggons with flangeless wheels were hauled by horses. The horizontal running track of the rails was 4 inches (100 mm) wide, and

2730-559: The Franklin Institute to conduct a study. As part of the study, Walter R. Johnson and Benjamin Reeves conducted strength tests on boiler iron using a tester they had built in 1832 based on a design by Lagerhjelm in Sweden. Because of misunderstandings about tensile strength and ductility, their work did little to reduce failures. The importance of ductility was recognized by some very early in

2800-536: The Middle Ages, iron was produced by the direct reduction of ore in manually operated bloomeries , although water power had begun to be employed by 1104. The raw material produced by all indirect processes is pig iron. It has a high carbon content and as a consequence, it is brittle and cannot be used to make hardware. The osmond process was the first of the indirect processes, developed by 1203, but bloomery production continued in many places. The process depended on

2870-634: The Smoile and Lount collieries. The construction and use of the tramway was permitted by an Act of Parliament of 25 May 1794. Ashby Canal Company decided on 21 August 1798, to contract Benjamin Outram , one of the founders of the Butterley Company in Derbyshire regarding the benefits of using a tramway instead of a canal. The company approved his recommendations in December 1798 and issued some notes regarding

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2940-468: The axles, the wheels could usually be adjusted slightly with washers. Level crossings could be made truly level, the carts being re-engaged with the flanges once across the roadway. Even older than plateways were wagonways , which used wooden rails. Despite its ancient appearance, the Haytor Granite Tramway , the track with ledges cut in stone blocks to produce a similar effect as tram plates,

3010-451: The bars were cut up, piled and tied together by wires, a process known as faggoting or piling. They were then reheated to a welding state, forge welded, and rolled again into bars. The process could be repeated several times to produce wrought iron of desired quality. Wrought iron that has been rolled multiple times is called merchant bar or merchant iron. The advantage of puddling was that it used coal, not charcoal as fuel. However, that

3080-413: The course of the smelt, slag would melt and run out, and carbon monoxide from the charcoal would reduce the ore to iron, which formed a spongy mass (called a "bloom") containing iron and also molten silicate minerals (slag) from the ore. The iron remained in the solid state. If the bloomery were allowed to become hot enough to melt the iron, carbon would dissolve into it and form pig or cast iron, but that

3150-454: The curved upright flange was 2 inches (50 mm) high in the centre and 3– 3 + 1 ⁄ 2 inches (75–90 mm) at the ends. The track was called “Outram Way”. The gauge of 4 ft 2 in ( 1,270 mm ) was 8 inches (200 mm) wider than that of Outram's earlier tramways, as he believed that this would offer additional capacity for the transporting of goods. Some of the embankments and cuts cans still be seen, as well as

3220-580: The development of the blast furnace, of which medieval examples have been discovered at Lapphyttan , Sweden and in Germany . The bloomery and osmond processes were gradually replaced from the 15th century by finery processes, of which there were two versions, the German and Walloon. They were in turn replaced from the late 18th century by puddling , with certain variants such as the Swedish Lancashire process . Those, too, are now obsolete, and wrought iron

3290-432: The fuel, and so is not contaminated by its impurities. The heat of the combustion products passes over the surface of the puddle and the roof of the furnace reverberates (reflects) the heat onto the metal puddle on the fire bridge of the furnace. Unless the raw material used is white cast iron, the pig iron or other raw product of the puddling first had to be refined into refined iron , or finers metal. That would be done in

3360-401: The gases were liberated. The molten steel then froze to yield a spongy mass having a temperature of about 1370 °C. The spongy mass would then be finished by being shingled and rolled as described under puddling (above). Three to four tons could be converted per batch with the method. Steel began to replace iron for railroad rails as soon as the Bessemer process for its manufacture

3430-430: The iron. The included slag in wrought iron also imparts corrosion resistance. Antique music wire , manufactured at a time when mass-produced carbon-steels were available, was found to have low carbon and high phosphorus; iron with high phosphorus content, normally causing brittleness when worked cold, was easily drawn into music wires. Although at the time phosphorus was not an easily identified component of iron, it

3500-486: The length to 6 feet (1.8 m) and, later, 9 feet (2.7 m), spanning several sleeper blocks In 1789, on a line between Nanpantan and Loughborough , Leicestershire , William Jessop used edge rails cast in 3-foot (0.9 m) lengths, with "fish-bellying" to give greater strength along the length of the rail. However, after he became a partner in Benjamin Outram and Company (Butterley Iron Works) he designed

3570-530: The line in 1802 and 1803. Their reports show the length of the completed sections as follows. The tramway was informally taken into use between July and October 1802. It was last used on 1913 and officially closed in 1915. The tramway is recognised as "well ahead of its time" and "a milestone in transport technology and a model for the modern railway systems which followed thirty years later." The L-shaped cast iron rails were cast in Benjamin Outram's foundry of

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3640-504: The mid 19th century, in Austria as the stuckofen to 1775, and near Garstang in England until about 1770; it was still in use with hot blast in New York in the 1880s. In Japan the last of the old tatara bloomeries used in production of traditional tamahagane steel, mainly used in swordmaking, was extinguished only in 1925, though in the late 20th century the production resumed on

3710-575: The next, and wait for oncoming traffic if necessary. However, others, such as the Surrey Iron Railway , the Kilmarnock and Troon Railway , the Monmouthshire Railway and Canal Company tramroads, and the Severn and Wye Railway , were wholly or partly double-track. Because they had un-flanged wheels, wagons that ran on plateways could also run on ordinary roads. Plateways tended to get obstructed by loose stones and grit, leading to wear. Edgeways avoid

3780-597: The plateway were made of cast iron , often fabricated by the ironworks that were their users. On most lines, that system was replaced by rolled wrought iron (and later steel ) "edge rails" which, along with realignment to increase the radius of curves, converted them into modern railways, better suited to locomotive operation. Plateways were particularly favoured in South Wales and the Forest of Dean , in some cases replacing existing edge rails. Other notable plateways included

3850-666: The product is no longer wrought iron, since the slag stringers characteristic of wrought iron disappear on melting, so the product resembles impure, cast, Bessemer steel. There is no engineering advantage to melting and casting wrought iron, as compared to using cast iron or steel, both of which are cheaper. Due to the variations in iron ore origin and iron manufacture, wrought iron can be inferior or superior in corrosion resistance, compared to other iron alloys. There are many mechanisms behind its corrosion resistance. Chilton and Evans found that nickel enrichment bands reduce corrosion. They also found that in puddled, forged, and piled iron,

3920-437: The rails or plates). The plates were usually made from cast iron and had differing cross sections , depending on the manufacturer. They were often very short, typically about 3 feet (0.9 m) long, able to stretch only from one block to the next. The L-section plateway was introduced for underground use in about 1787, by John Curr of Sheffield Park Colliery. Joseph Butler , of Wingerworth near Chesterfield , constructed

3990-504: The route. In December 1799 the company concluded that it could not finance a double-track line, and built just a single-track line from Old Parks Tunnel to Ticknall but a double-track from Willesley to Old Parks. Due to the lack of liquidity, Outram threatened the company in February 1801 to stop all work if he was not paid. The company complained about Outram's workmanship and contracted Joseph Wilkes of Measham and other inspectors, to assess

4060-531: The same manner as mild steel, but the presence of oxide or inclusions will give defective results. The material has a rough surface, so it can hold platings and coatings better than smooth steel. For instance, a galvanic zinc finish applied to wrought iron is approximately 25–40% thicker than the same finish on steel. In Table 1, the chemical composition of wrought iron is compared to that of pig iron and carbon steel . Although it appears that wrought iron and plain carbon steel have similar chemical compositions, that

4130-401: The stone obstruction problem. Stone blocks had an advantage over timber sleepers because they left the middle of the track unhindered for the hooves of horses , but timber sleepers had an advantage over stone blocks because they prevented the track from spreading. The gauges of some tramroads increased by a couple of inches after decades of horses passing up the middle but, being loose on

4200-465: The top of the puddle and was fished out of the melt as puddle balls, using puddle bars. There was still some slag left in the puddle balls, so while they were still hot they would be shingled to remove the remaining slag and cinder. That was achieved by forging the balls under a hammer, or by squeezing the bloom in a machine. The material obtained at the end of shingling is known as bloom. The blooms are not useful in that form, so they were rolled into

4270-560: The working-over of the metal spread out copper, nickel, and tin impurities that produce electrochemical conditions that slow down corrosion. The slag inclusions have been shown to disperse corrosion to an even film, enabling the iron to resist pitting. Another study has shown that slag inclusions are pathways to corrosion. Other studies show that sulfur in the wrought iron decreases corrosion resistance, while phosphorus increases corrosion resistance. Chloride ions also decrease wrought iron's corrosion resistance. Wrought iron may be welded in

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4340-479: Was adopted (1865 on). Iron remained dominant for structural applications until the 1880s, because of problems with brittle steel, caused by introduced nitrogen, high carbon, excess phosphorus, or excessive temperature during or too-rapid rolling. By 1890 steel had largely replaced iron for structural applications. Sheet iron (Armco 99.97% pure iron) had good properties for use in appliances, being well-suited for enamelling and welding, and being rust-resistant. In

4410-484: Was considered sufficient for nails . Phosphorus is not necessarily detrimental to iron. Ancient Near Eastern smiths did not add lime to their furnaces. The absence of calcium oxide in the slag, and the deliberate use of wood with high phosphorus content during the smelting, induces a higher phosphorus content (typically <0.3%) than in modern iron (<0.02–0.03%). Analysis of the Iron Pillar of Delhi gives 0.11% in

4480-415: Was contemporary with plateways, being built in 1820. Wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which give it a wood-like "grain" that is visible when it is etched, rusted, or bent to failure . Wrought iron

4550-515: Was hypothesized that the type of iron had been rejected for conversion to steel but excelled when tested for drawing ability. During the Han dynasty (202 BC – 220 AD), new iron smelting processes led to the manufacture of new wrought iron implements for use in agriculture, such as the multi-tube seed drill and iron plough . In addition to accidental lumps of low-carbon wrought iron produced by excessive injected air in ancient Chinese cupola furnaces . The ancient Chinese created wrought iron by using

4620-471: Was moved to the Blists Hill site of Ironbridge Gorge Museum for preservation. Some wrought iron is still being produced for heritage restoration purposes, but only by recycling scrap. The slag inclusions, or stringers , in wrought iron give it properties not found in other forms of ferrous metal. There are approximately 250,000 inclusions per square inch. A fresh fracture shows a clear bluish color with

4690-445: Was not the intention. However, the design of a bloomery made it difficult to reach the melting point of iron and also prevented the concentration of carbon monoxide from becoming high. After smelting was complete, the bloom was removed, and the process could then be started again. It was thus a batch process, rather than a continuous one such as a blast furnace. The bloom had to be forged mechanically to consolidate it and shape it into

4760-528: Was of little advantage in Sweden, which lacked coal. Gustaf Ekman observed charcoal fineries at Ulverston , which were quite different from any in Sweden. After his return to Sweden in the 1830s, he experimented and developed a process similar to puddling but used firewood and charcoal, which was widely adopted in the Bergslagen in the following decades. In 1925, James Aston of the United States developed

4830-509: Was taken up in 1861 by the Toronto streetcar system . Horsecars ran on the upper, outer part as edgerail, with the wheel flanges on the inside. The edge rail formed an outside flange for a broad foot which allowed wagons to pass through the unmade streets. That combination necessitated a unique, broader gauge of 4 ft  10 + 7 ⁄ 8  in ( 1,495 mm ) known as the Toronto gauge . The early plateways were usually operated on

4900-473: Was the chemical composition and others that it was whether the iron heated sufficiently to melt and "fuse". Fusion eventually became generally accepted as relatively more important than composition below a given low carbon concentration. Another difference is that steel can be hardened by heat treating . Historically, wrought iron was known as "commercially pure iron"; however, it no longer qualifies because current standards for commercially pure iron require

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