Metallurgy Group

1. Metallurgy Group • David Dobbs • Scott Jones • Minh Nguyen • Marc Rubin

2. Objectives • Extract metals from ore • Create efficient die • Create coin using the metal

3. Procedure • History of making bronze • Make crucible from clay • Measure amount of chemicals • Metallurgy, using bronze to make coins.

4. History of Bronze • First signs of Bronze • Uses of Bronze in Ancient cultures • Methods of making Bronze -ancient -modern • Fun Facts • “Bronze”. Microsoft Encarta Online Encyclopedia 2001. http://encarta.msn.com (25 Sept. 2001).

5. First Signs of Bronze • 3500 BC-First created by the ancient Sumerians. • 3000 BC-Bronze spreads to Persia. • 2000 BC-Bronze in China and Egypt. • 650 BC-330 AD- Hellenistic culture uses bronze. • “Bronze”. Microsoft Encarta Online Encyclopedia 2001. http://encarta.msn.com (25 Sept. 2001).

6. Use of Bronze • Ancient use: The accidental discovery of bronze in cooking fires. • China: Pour metal into molds for spoons and/or pottery. • Greece/Rome: Used to forge coins and make weapons.

7. Bronze making process • Ancient: accidentally made when rocks with natural tin and copper ore were used as the campfire ring. • Modern: The tin and copper are first “roasted”- blowing oxygen across the heated metal ore to get rid of impurities. • Both: heat until over 1000°C to combine the 2 metals.

8. Fun Facts • The bronze our group constructed destroyed steel. • We used 15 tons of pressure from a hydraulic pump to mash the bronze into a coin between 2 plates of steel. • End result: the bronze made a lasting indention in steel: (picture)

9. 15 tons of pressure + bronze = destroyed steel

10. Making a Crucible • From dirt to clay. • Shaping your crucible. • Dry it. • Add the chemicals. • FIRE!

11. From Dirt to Clay • Grinding the dirt into powder. • Adding water.

12. Shaping Your Crucible • Different methods presented to us.

13. Dry it • Leaving it out over night. • Drying in the oven.

14. Add the Chemicals • Layering the chemicals.

15. FIRE! • The kiln. • Chemical reactions.

16. Mixing Chemicals • We Want to obtain bronze. • Mix copper carbonate(CuCO3) and tin oxide(SnO) in a 5:1 ratio • Weigh chemical compounds -5 g.CuCO3 and 1 g. SnO -3 g. of Na2CO3 -5 grams of charcoal (C)

17. Mixed Chemicals CuCO3 and SnO Charcoal (C) Na2CO3

18. Placing Compounds in Crucible • Lowest layer mixture of CuCO3 and SnO • Middle layer, flux Na2CO3 • Top layer, charcoal

19. Chemical Equations • 2 CuCO3(s) + C(s) 2 Cu(s) + 2 CO2(g) • 2 SnO(s) + C(s)  2 Sn(s) + CO2(g) • Compounds layered in crucible are placed in kiln • The compounds are heated in an oxidizing atmosphere at 1000 °C.

20. Chemical Equation Cont. • Na2CO3 is used as a fluxing agent • Pure metal ores, copper and tin come together to form bronze.

21. Eureka • We have created a metal bead from the ore.

22. Making the Die • Anything etched in the die will create a mirror image. • We made a smilie face on one side and “CC” on the other side.

24. Making the Die • We used a punch, drill and chisel to etch our image into the end of the punch.

25. Striking the Coin • It was necessary to heat the metal bead with a torch. • Then we whacked it.

26. FINAL PRODUCT Just kidding

27. Final Product