USES FOR TYPES OF STEELS

¥ Low carbon steel (0.08 - 0.35 % carbon) is ductile with low brittleness. It is is used for ANCIENT IRON auto body parts, home appliances, tin cans, I beams for construction. AND STEEL ¥ Medium carbon steel (0.35 - 0.5 % carbon) (Part II) is used as crankshaft, gears, railroad axels. (Part II) They are difficult to weld. ¥ High carbon steel (> 0.5 % carbon) is used for railroad wheels and rails, wrenches, steel cable, tools, dies, piano wire etc.

BLAST FURNACE CAST IRON (PIG IRON)

¥ Contains 1.5 - 5 % carbon. ¥ Its melting point is 1130 oC. ¥ The metal will shatter with a hard blow. ¥ Carbon in the form of graphite exists as flakes ¥ Graphite serves as a lubricant (excellent bearing material).

1 Cast Grey Iron Blast furnace at Cast Grey Iron Karabük Iron works

Cast Gray Iron

Graphite flakes

THE FINERY CAST IRON OBJECTS THE FINERY

Cast cannon 15th. Cent.

2 INDIRECT METHOD OF STEEL BESSEMER PROCESS PRODUCTION (THE BESSEMER PROCESS)

Crude cast iron from the blast furnace is remelted in a hearth (the finary) and subjected to a forced draught of air. The excess carbon is oxidized to carbon dioxide. The refined pig iron which is called malleable iron is now ready for final forging.

BESSEMER PROCESS FORMS OF IRON

CAST IRON Decarburization From Blast Furnace M.P. 1130oC 1,5-4.5 % C Bessemer STEEL Process M.P. 1400o C 0.1-0.9 % C

WROUGHT IRON From Bloomery Cementation M.P 1535o C 0.06 % C Carburization

3 DIFFERENCES BETWEEN BLOOMERY ALLOY STEELS AND BLAST FURNACE ¥ Increase in temperature (1300 - 1400oC) ¥ Alloy steel describes steel that contain one or more alloying elements in addition to carbon. ¥ Higher fuel to ore ratio yields CO/CO ratio 2 1. Low alloys: additions are <2%. over 90%. 2. Medium alloys: additions are Between 2-10%. ¥ Constituents of slag fayalite (Fe2SiO4) and 3. High alloy: additions are <10%. wustite (FeO) reduce to metallic iron. ¥ Common elements that are added are: Al, Cr, Co, ¥ Lime and/or clay added as flux to create slag Cu, Pb, Mn, Mo, Ni, P, Si, S, Tim W, and V. ¥ In all cases carbon content in < 1%.

CHINESE IRON TECHNOLOGY CHINESE CAST IRON

¥ Cast iron was produced in China sometime in the 7th or 6th century BC. (2000 years before west) ¥ This was due to: Advanced skill of bronze founders Effective furnace design Good refractory clay Efficient double action piston bellows Use of water power for bellows Use of good quality coal that contains phosphorus

4 DURSUN USTA, ÖMERLİ

5 METAL SMITH AT KANDIRA

6 7 SOUGUS IRON WORKS

THE FURNACE

8 WATER WHEEL

BELLOW FOR BLAST FURNACE

9 SAND CASTING MOLDS Furnace charge used at Saugus iron works

POWER HAMMER POWER HAMMER

10 THE FINERY IRON PRODUCT

ROLLING MILL PRODUCTS

11 IRON CASTING WORKSHOP

12 REPLICATING DAMASCUS BLADE

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