The material. In Victorian times people washed their clothes in a "copper"—a vat or tank of beaten copper sheet, heated over a fire. The device exploited both the high ductility and the thermal conductivity of the material. Copper has a distinguished place in the history of civilization: it enabled the technology of the Bronze Age (3000-1000 BC). It is used in many forms: as pure copper, as copper-zinc alloys (brasses), as copper-tin alloys (bronzes), and as copper-nickel and copper-beryllium. The designation of copper is used when the percentage of copper is more than 99.3%.
Composition Cu with up to 40% Zn or 30% Sn, Al or Ni. General properties
|
Mechanical properties Young’s modulus |
112 |
– 148 |
GPa |
Yield strength (elastic limit) |
30 |
– 350 |
MPa |
Tensile strength |
100 |
– 400 |
MPa |
Elongation |
3 |
– 50 |
% |
Hardness—Vickers |
44 |
– 180 |
HV |
Fatigue strength at 107 cycles |
60 |
– 130 |
MPa |
Fracture toughness |
30 |
– 90 |
MPa. m1/2 |
Thermal properties |
||
Melting point |
982 – 1080 |
°C |
Maximum service temperature |
180 – 300 |
°C |
Thermal conductor or insulator? |
Good conductor |
|
Thermal conductivity |
160 – 390 |
W/m. K |
Specific heat capacity |
372 – 388 |
J/kg. K |
Thermal expansion coefficient |
16.9 – 18 |
p, strain/°C |
Electrical properties |
||
Electrical conductor or insulator? |
Good conductor |
|
Electrical resistivity |
1.74 – 5.01 |
pnhm. cm |
Copper and brass are exceptionally ductile and can be worked into complex shapes.
Typical uses. Electrical wiring, cables, bus bars, high strength, high conductivity wires and sections, overheads lines, contact wires, resistance-welding electrodes, terminals, high-conductivity items for use at raised temperatures, heat exchangers, coinage, pans, kettles and boilers, plates for etching and engraving, roofing and architecture, cast sculptures, pumps, valves, marine propellers.