Copper is one of the oldest elements known to humanity, and its importance in modern applications cannot be overstated. It is soft and malleable, easily bent into any shape. Copper also has excellent corrosion resistance, maintaining good performance even when exposed to harsh environments for long periods, making it a reliable material for long-term use.
Today, we will discuss some of copper's other fascinating properties: its magnetism and conductivity.
Does copper attract a magnet?
Atoms have spinning nuclei and orbiting electrons that create micro-magnetic fields. For an atom to be magnetic, its outer electron shell must not be full. Only certain elements like iron and nickel form magnetic crystals, while non-magnetic metals like copper do not.
- Copper is a non-magnetic material, specifically diamagnetic, meaning it repels when brought close to a magnet. The magnetism of copper is related to its atomic structure. To form metallic bonds, it shares a single unpaired electron in the 4s orbital (paramagnetism), leading to its diamagnetism.
- The relative magnetic permeability of copper is very close to 1 (mr=0.9999912), indicating a very weak influence on magnetic fields.
- The magnetic susceptibility of copper is cm=-8.88×10-6, showing its diamagnetic nature.
- As temperature rises, the magnetism of copper weakens.
Why is copper a good conductor?
Copper is a good conductor material because of the following reasons：
- Free Electrons: Copper's atomic structure has free electrons in the outermost shell that can move within the metal, forming an electric current.
- Band Structure: In copper's band theory, the valence and conduction bands overlap, allowing electrons to easily jump from the valence to the conduction band, thus conducting electricity.
- Low Resistance: The atomic nuclei of copper weakly bind the outermost electrons, so there is less resistance to electron movement within the metal, resulting in low resistance.
- Good Thermal Conductivity: Copper has good thermal conductivity, which allows for quick heat dissipation, maintaining a stable working temperature, crucial for electrical transmission.
- Corrosion Resistance: Copper resists oxidation, corrosion, and embrittlement, maintaining good conductive performance in various environments.
- Softness and Ductility: Copper is soft and ductile, easily bent and shaped, and suitable for installation in cable conduits.
Table 1. Comparison of resistivity and conductivity of copper and other metals
Material | Resistivity | Conductivity |
Silver | 1.59×10-8 | 6.30×107 |
Copper | 1.68×10-8 | 5.96×107 |
Gold | 2.44×10-8 | 4.10×107 |
Aluminum | 2.82×10-8 | 3.5×107 |
Calcium | 3.36×10-8 | 2.98×107 |
5.60×10-8 | 1.79×107 | |
Zinc | 5.90×10-8 | 1.69×107 |
Nickel | 6.99×10-8 | 1.43×107 |
Copper and copper alloy products
There are over 400 types of copper alloys, each with a unique combination of properties to suit a multitude of applications, manufacturing processes, and environments.
- Brass： It refers to a series of copper-zinc alloys that combine different properties, known for their good mechanical properties and corrosion resistance, often used in decorative items, valves, and fittings.
- Bronze: Typically refers to tin-containing copper alloys, known for their strength and wear resistance, suitable for bearings, gears, and sculptures.
- Cupronickel: A copper alloy with nickel as the main additive element, noted for its excellent corrosion resistance and attractive appearance, commonly used in coins, medical instruments, and marine engineering.
What do tin and copper make?
- Electronic components: As copper-tin alloys have good electrical and thermal conductivity, they are widely used in the manufacture of electronic components.
- Mechanical parts: As copper-tin alloys have high wear resistance and corrosion resistance, they can be used to manufacture bearings, gears, piston rings, and other parts.
- Automobile parts: As copper-tin alloys have good wear resistance and fatigue resistance, they can be used to manufacture automobile parts, such as engine parts, transmission system parts, braking system parts, and so on.
- Military equipment: As copper-tin alloy has good mechanical and electromagnetic properties, it is widely used in the manufacture of military equipment, such as radar antennae, communication equipment, and missile components.
With the continuous development and advancement of technology, 3D printing techniques are becoming increasingly mature, leading to the ongoing development of materials for 3D printing. High-quality spherical copper powder and spherical bronze powder, known for their excellent flowability and high density, are widely used in 3D printing technologies. They are particularly utilized in powder bed fusion techniques such as Selective Laser Melting (SLM) and Electron Beam Melting (EBM) to create complex structures with good electrical conductivity and thermal conductivity.
Copper's unique properties make it an indispensable player in modern technology. As technology continues to advance, copper's applications in energy transmission, electronic devices, and smart technologies are becoming increasingly extensive. It will not only support the development of sustainable energy but also aid in the innovation of a new generation of technologies.
Heeger Materials is a reputable supplier offering various kinds of high-quality Spherical Powder products at competitive prices, which are widely used in research and science fields. If you're interested, feel free to contact us at [email protected] for a quote, and we guarantee a response within 24 hours.