A Brief History of Materials Science & Engineering

by P.Loos Jan. 2004

c. 8000 BC  - First use of Cu, in the area we presently call Iraq.  Found in rock formations in the metallic state, dug up and beaten into shape, to form tools, ornaments, etc..  About this same time the first farming villages appear.

c. 5000 BC  - Pottery made and Cu extracted from its ore.  These two materials technologies are related.  High temperatures are needed to extract metal from ore, more than just sticks of wood and an open fire.  Pottery ovens, properly ventilated, provided the needed temperatures.  About this same time gold was discovered, dug up out of the ground and beaten into various shapes.

c. 3500 BC  - Hardening of Cu with Sn.  Beginning of the Bronze Age.  The alloy is considerably stronger than the pure metals.

c. 1500 BC  - Production of metallic iron from its oxide ore.  This requires temperatures considerably higher than extraction of Cu and requires charcoal as a reducing agent.  This was first done by the Hittites in present-day Turkey.  Fe has important advantages over Cu:  It is much more common and cheaper.  The Fe-C alloy is much harder and stronger than Cu alloys so one can produce better tools and weapons with sharper edges.  Knowledge of Fe smelting was so valuable that the Hittite kings apparently restricted the export of Fe weapons and kept secret their ironworking techniques.  The Iron Age led to many changes in society.  With a sharp Fe axe one could chop down trees more easily for building wooden houses.  This led to the deforestation of much of Europe.

c. 1200BC - Earliest quenching and tempering of steel to harden it.  Steel is an alloy of Fe and C.  This began in Greece.  Homer refers to this process in his Odyssey, describing the blinding of Cyclops.

c. 900 BC - Hardened steel tools & weapons were in widespread use, displacing the older bronze technology.

c. 1903 - Precipitation hardening of Al, the first nano-technology.  This process is often referred to as age hardening.  The Wright Bros. used an alloy of Al + 8wt% Cu for the engine in their plane.  Fe engines were too heavy to get off the ground.  Similar Al-Cu alloys have been used extensively in the aircraft industry ever since, for the main structure and skin of the aircraft. In the literature you will often see this discovery attributed to Alfred Wilm who published a paper on the subject in 1911 and received a patent.

The production and heat treatment of Fe-C alloys and Al-Cu alloys are among the greatest technological developments in human history.  These developments have had a huge impact on society and our standard of living.

Note:  Your instructor has lost his notes which included references to the published literature; however, much of this can also be found on the internet using a good search engine.