Copper properties
Copper is a pure metal prized above all for its outstanding electrical and thermal conductivity, second only to silver. It is soft, ductile, and corrosion resistant. Values below are for annealed electrolytic tough-pitch copper.
Mechanical properties
| Property | Value |
|---|---|
| Yield strength | 10 ksi (69 MPa) |
| Ultimate tensile strength | 32 ksi (220 MPa) |
| Elongation | 45% |
| Hardness | about 45 HB (Brinell) |
| Modulus of elasticity | 17,000 ksi (117 GPa) |
Physical properties
| Property | Value |
|---|---|
| Density | 0.323 lb/in³ (8940 kg/m³) |
| Melting point | 1085 °C |
Thermal properties
| Property | Value |
|---|---|
| Thermal conductivity | 391 W/m·K |
| Thermal expansion | 16.5 µm/m·°C |
| Specific heat | 385 J/kg·K |
Values are typical for the grade and condition shown. Actual properties vary with temper, heat treatment, and product form, so use these for comparison and preliminary design and confirm against material certificates for final work.
Compare with other materials
See the Material Properties Comparison, Yield Strength, and Density charts.
Typical uses
Copper is used for electrical wiring, busbars, motor windings, heat exchangers, plumbing, and roofing. Its superb conductivity makes it the standard for carrying current and heat, and its corrosion resistance and ductility suit piping and sheet.
How it compares
No common metal conducts electricity or heat better than copper except silver, which is far costlier. Copper is much softer and weaker than its brass and bronze alloys, which trade some conductivity for strength, machinability, and wear resistance.
FAQ
Why is copper used for wiring?
It has very high electrical conductivity, second only to silver, so it carries current with low losses, and it is ductile enough to draw into wire.
Does copper corrode?
It resists corrosion well, forming a protective patina over time. This is why copper roofs and pipes last for decades.
Is copper strong?
Pure copper is soft and weak. Alloying it into brass or bronze greatly increases strength and wear resistance at some cost in conductivity.