Copper’s enhanced hardness under extreme strain

• Strain: Deformation of material under stress.
• Strain rate: Rate at which strain changes, measured per second.

• Basics: Metals become softer when heated and strained at certain rates (0.000001/s and 10,000/s).
• SAE 304 steel is the most common form of stainless steel today.

Copper

• It is a good conductor of electricity and is ductile [able to be drawn out into a thin wire].
• Alloys of Copper
  • Iron + chromium + nickel with carbon +silicon + manganese = Stainless Steel.
  • Copper + Nickel == Morel Metal.
  • Copper + Aluminium == Duralumin.
  • Copper + Zinc == Brass.
  • Copper + Tin == Bronze.
• Copper ore is found in ancient as well as in younger rock formations.
• Mining for copper is costly because most of the copper ores contain a small percentage of the metal.
• India has low-grade copper ore (less than 1% metal content, international average 2.5%).
• The major part of supply comes from the USA, Canada, Zimbabwe, Japan and Mexico.

Stone Age to Metal Age: Evolution of Metals

• End of Stone Age: Copper smelting and alloying. Introduced metalworking, better agricultural tools, culture, trade, governments, and new weapons.
• Iron Age: Iron replaced copper and tin.
  • Steel is made by adding carbon to iron. Iron’s unique property is that it dissolves carbon. Repeated heating and cooling with carbon produces steel, a hard iron-carbon alloy.
  • Impact of Steel: Harder than copper, tin, or iron.