1. Pre-History
Stone
Flint
Wood

2. 20,000 BCE Gold Easy to form (Malleable)
Although 20,000 BCE is an estimate, gold is the earliest metal to be processed by humans.

3. 7,000 BCE
Copper, Silver
Native metals (gold, copper, silver) were discovered and found to be ductile thus easy to form

4. 5,000 BCE Pottery Cement Glass Smelted copper
Heating and reducing substances (like charcoal) that react with the oxidizing elements

5. 3,500 BCE Tin Bronze Alloy of Copper and Tin.
Earliest Bronze pieces had about 2% tin, suggesting it was an accident
Later tin content increased and suggests intention

6. 3,000 BCE Papyrus Second polymer in use (after wood)
First processed polymer
Stems of papyrus plant are stripped, rotted (retted), and pressed into a polymer sheet

7. 1,500 BCE Iron Needs higher temperature than bronze
Much more abundant than copper

8. 1,000 BCE
Lacquer
Extracted from tree sap
Used to preserve wood

9. 100 BCE – 100 CE Amber Horn Paper
Starting to develop more methods of extracting natural resources and converting to modern needs

10. 800 CE
Gutta percha
Natural latex is produced from the sap of the percha
Bioinert, resilient good electrical insulator
Sap was left in sun to evaporate, leaving thermoplastic latex

11. 1000 CE
Crucible steel
Iron + carbon

12. 1500 CE
Iron smelting
Rubber

13. 1700 CE Platinum Cobalt Zinc Nickel Tungsten Zirconium Uranium
Strontium
Titanium

14. 1800-1850 Magnesium Aluminum Silicon Cellulose Nitrate
Flash paper, guncotton
Vulcanized rubber
Reinforced concrete

15. 1850-1900 Ebonite Bessemer steel Glass fiber Cellulose acetate
First inexpensive purification method
Glass fiber
Cellulose acetate
Aluminum oxide

16. 1900-1920 Bakelite Stainless steel Synthetic rubber Nylon
First truly synthesized polymer
Thermoset phenol formaldehyde
Stainless steel
Synthetic rubber
Nylon

17.
Neoprene
PMMA
PVC PU
PET
PTFE
Plutonium

18. 1940-1960 Formica Lycra PS Composites Super alloys Acetal POM PC PP
Amorphous metals
Metallic glasses

19. 1960-1980 Polyimides Polysulfone PPO LLDPE Shape memory alloys
Carbon fiber

20.
PEEK
PES
PPS
Warm superconductors
Nano materials
Biopolymers

21. Reliance on materials We are totally dependent on materials
We have shifted from renewable to non-renewable
Transportation, communications, ordinance

23. Materials Consumption
About 10 tons per person per year in US
Thomas Malthus, 1798:
The power of population is so superior to the power of the Earth to produce subsistence for man that premature death must in some shape or other visit the human race.

24. Consumption Club of Rome (1972)
…if [current trends] continue unchanged … humanity is destined to reach the natural limits of development within the next 100 years.

25. Is this the end?
World Commission on Environment and Development (1987)
many aspects of developed societies are approaching saturation, in the sense that things cannot go on growing much longer without reaching fundamental limits. This does not mean that growth will stop in the next decade, but that a declining rate of growth is foreseeable in the lifetime of many people now alive. In a society accustomed to 300 years of growth, this is something quite new, and will require considerable adjustment.

26. Competence
Humans differ from other species in our competence to make things from materials
Termites, beavers, birds, etc. make things
Difference is competence shown by humans
Ability to expand and adapt through research and development
Are materials the servant or master?

27. Exercise
It takes energy to make materials, called “embodied energy” and expressed in terms of the energy per unit mass (MegaJoules/kilogram = MJ/kg).
If you could reduce consumption by 10%, rank the following 5 Engineering materials in order of greatest global energy savings to least.
Explain your conclusions and show calculations to support them.
Details on next page show embodied energy and total tons (1,000 kg) consumed in a year.

28. Material
Embodied Energy (MJ/kg)
Annual Global Consumption (tons/year)
Steels 29
1.1 billion
Aluminum alloys
200
32 million
Polyethylene 80
68 million
Concrete
1.2
15 billion
Device grade silicon
2,000
5,000