Wrought iron

A remarkable iron pillar, dating to about A.D. 400, remains standing today in Delhi, India. This solid shaft of wrought iron is about 71/4 m high by 40 cm in diameter. Corrosion to the pillar has been minimal although it has been exposed to the weather since its erection. 

Iron is hard, brittle, fairly fusible, and is used to produce other alloys, including steel. Wrought iron contains only a few tenths of a percent of carbon, is tough, malleable, less fusible, and has usually a "fibrous" structure. 

Fig. 10. 1000 h stress—rupture curves of wrought cobalt-base (Haynes 188 and L-605) and wrought iron-base superalloys (49). To convert MPa to psi,... 

It has been known for many centuries that iron ore, embedded in burning charcoal, can be reduced to metallic iron (1,2). Iron was made by this method as early as 1200 BC. Consisting almost entirely of pure iron, the first iron metal closely resembled modem wrought iron, which is relatively soft, malleable, ductile, and readily hammer-welded when heated to a sufficientiy high temperature. This metal was used for many purposes, including agricultural implements and various tools. 

It was not until the eighteenth century that carbon was recognized as a chemical element, and it is quite certain that no early metallurgist was aware of the basis of the unique properties of steel as compared to those of wrought iron. Carbon can be alloyed with iron in a number of ways to make steel, and all methods described herein have been used at various times in many locaUties for perhaps 3000 or more years. 

Although 10—30-t nuld-steel or wrought-iron pot stills, equipped with fractionating columns, are stiU in use at one tar works in Spain, continuous stills that have daily capacities of 100—700 t are preferred and used exclusively in the rest of the world. 

Galorized surfaces, heated at lllO F. Wrought iron, dull oxidized 70-680 0.94... 

From Moody, Trans. Am. Soc. Mech. Eng., 66, 671-684 (1944) Mech. Eng., 69, 1005-1006 (1947). Additional values of e for various types or conditions of concrete wrought-iron, welded steel, riveted steel, and corrugated-metal pipes are given in Brater and King, Handbook of Hydraulics, 6th ed., McGraw-Hill, New York, 1976, pp. 6-12-6-13. To convert millimeters to feet, multiply hy 3.281 X l0- ... 

Cold water Warm water Wrought iron Air bubbled into water surrounding coil 150-300... 

Cold water 25% oleum at 60 C. Wrought iron Agitated 20... 

With the fall of the Roman Empire, the ancient water supplies petered out. In early medieval times, people were content to conduct local water in wooden pipes to public cisterns. The first wooden pipelines for water were laid at Liibeck about 1293 and in 1365 at Nuremberg. In 1412 the Augsburg master builder Leopold Karg first used wrought-iron pipes in conjunction with wooden pipes to supply water. Because of their propensity to corrosion, they seem to have proved a failure and a few years later they were exchanged for wooden, lead, and cast-iron pipes. 

Schmiedeeisen, n. wrought iron forging steel, mild steel. 

Schmiedeisen, n. = S -hmiedeeisen, schmiedeisern, [Pg.393]

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