Ancient Regional Steel Quality: Historical Methods of Steel Production Around the World

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Ancient Regional Steel Quality: Historical Methods of Steel Production Around the World ANCIENT REGIONAL STEEL QUALITY: HISTORICAL METHODS OF STEEL PRODUCTION AROUND THE WORLD An Interactive Qualifying Project Report Submitted to the Faculty Of the WORCESTER POLYTECHNIC INSTITUTE By Ian De Lisle William Gorman Christopher Jackson Matt Murphy Samuel Young Date: March 11, 2016 Submitted to: Professor Diana A. Lados Mr. Tom H. Thomsen Table of Contents Table of Contents ................................................................................................................ 2 List of Figures ..................................................................................................................... 4 Individual Participation ....................................................................................................... 6 Authorship........................................................................................................................... 7 1. Abstract .......................................................................................................................... 9 2. Introduction .................................................................................................................. 10 3. European Smelting ....................................................................................................... 11 3.1 Background ............................................................................................................. 11 3.2 The Bloomery Furnace ............................................................................................ 12 3.3 The Cultural Impact of Steel in Europe .................................................................. 16 3.3.1 Steel and Religion............................................................................................. 16 3.3.2 Social Hierarchy of Steel .................................................................................. 18 3.3.3 Steel and Trade ................................................................................................. 20 3.3.4 Weapons and Armor in Europe ........................................................................ 22 4. Steel Production in India .............................................................................................. 26 4.1 Background ............................................................................................................. 26 4.2 The Production of Crucible Steel ............................................................................ 27 4.3 Cultural Impact of Steel in India ............................................................................. 34 4.3.1 Steel and Religion............................................................................................. 34 4.3.2 Social Hierarchy of Steel .................................................................................. 34 4.3.3 Steel and Trade ................................................................................................. 35 4.3.4 Weapons and Armor of India ........................................................................... 36 5. Japanese Smelting ........................................................................................................ 37 5.1 Background ............................................................................................................. 37 5.2 The Tatara Furnace .................................................................................................. 38 5.3 The Cultural Impact of Steel in Japan ..................................................................... 43 5.3.1 Steel and Religion............................................................................................. 43 5.3.2 Social Hierarchy of Steel .................................................................................. 45 5.3.3 Steel and Trade in Japan ................................................................................... 47 2 5.3.4 Japanese Arms and Armor................................................................................ 49 6. Comparison of All Three Regions ............................................................................... 53 6.1 Religious Comparisons ........................................................................................... 53 6.2 Trade and War Comparisons ................................................................................... 54 6.3 Quantity and Quality of Materials Produced ........................................................... 55 7. Material Properties ....................................................................................................... 57 7.1 Material Science Background ................................................................................. 57 7.2 Predicted Material Properties .................................................................................. 58 7.2.1 Material Cooling Rate ...................................................................................... 59 7.2.2 Phase Calculations Using the Lever Rule ........................................................ 60 7.3 Microstructural Characterization ............................................................................. 61 8. Our Research ................................................................................................................ 65 8.1 Acquiring the materials ........................................................................................... 65 8.2 Constructing the furnace ......................................................................................... 68 8.3 Smelting the Iron ..................................................................................................... 74 8.4 Preparing Samples of the Iron Bloom ..................................................................... 84 8.4.1 Mounting and polishing .................................................................................... 85 8.4.2 Final Polishing .................................................................................................. 85 8.4.3 Etching .............................................................................................................. 86 8.5 Microstructural Analysis of the Iron Bloom ........................................................... 87 9. Conclusion ................................................................................................................... 93 Works Cited ...................................................................................................................... 95 APPENDIX A ................................................................................................................. 100 APPENDIX B ................................................................................................................. 114 3 List of Figures Figure 1. The base of the furnace...................................................................................... 12 Figure 2. An example of an iron bloom. ........................................................................... 15 Figure 3. Volga and Byzantine trade routes in the 11th century. ..................................... 21 Figure 4. Excerpt from “Natural Magick”. ....................................................................... 23 Figure 5. Gauntlets of Emperor Maximilian I. ................................................................. 24 Figure 6. Polish War Picks............................................................................................... 25 Figure 7. Carbide Patterns in Damascus Steel. ................................................................. 26 Figure 8. A modern reproduction of an Indian or Middle Eastern furnace. ..................... 28 Figure 9. Grain structure of Ultra High Carbon Steel (UHCS). ....................................... 29 Figure 10. A historical blacksmith Fe3C phase diagram ................................................... 30 Figure 11. A modern Fe3C phase diagram ........................................................................ 31 Figure 12. Indian Tulwar. ................................................................................................. 32 Figure 13. Persian Scimitar. .............................................................................................. 36 Figure 14. A tatara furnace (Inoue, 194). .......................................................................... 38 Figure 15. Impurities in tatara steel (Inoue, 196).............................................................. 39 Figure 16. Effects of trade elements on alloys (Industrial Heating RSS, 2). .................... 40 Figure 17. Tatara furnace stages 1 and 2 (Kitamura, 278). ............................................... 41 Figure 18. Tatara furnace stages 3 and 4 (Kitamura, 278). ............................................... 42 Figure 19. Impurities in Tamahagane steel (Inoue, 196). ................................................. 43 Figure 20. Variations in size of the tatara furnace (“About Tatara”, 1). .......................... 45 Figure 21. Ironsand ready for the tatara (Inoue, 194). ...................................................... 46 Figure 22. Forging tamahagane steel (Inoue, 195). .......................................................... 50 Figure 23. Samurai armor (Military Protection in Japan, 1). ............................................ 51 Figure 24. Lamellar plates (Military Protection in Japan, 1). ........................................... 52 Figure 25. Fe-Fe3C
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