Aluminum is a widely used metallic element in several different industries, but the extent to which it conducts electricity is often a topic of some confusion. In this article, we will be exploring the properties of aluminum and examining how it conducts electricity.
What is Aluminum?
Aluminum is an element on the periodic table with the symbol Al and atomic number 13. It was first discovered in 1825 by Danish physicist Hans Christian Oersted. Although, it was only identified as an individual element in 1827 by German chemist Friedrich Wohler. Aluminum is a silvery-white, soft, non-magnetic metal that is known for its low density and ability to resist corrosion.
Does Aluminum Conduct Electricity?
Aluminum is an excellent conductor of electricity. It has a conductivity of 37.7 million Siemens per meter (MS/m), which is about 61% of the conductivity of copper. This means that aluminum can conduct electricity almost as well as copper, which is widely recognized as one of the best electrical conductors.
The conductivity of aluminum is due to its high number of free electrons and its low atomic mass. In the solid state, aluminum atoms are arranged in a lattice structure, with each atom surrounded by a cloud of electrons. Because of the weak attraction between the positively charged atomic nuclei and the negatively charged electrons, some of these electrons can move freely through the lattice. When a voltage is applied across a piece of aluminum, these free electrons can move through the metal, carrying the electrical charge with them. This movement of electrons through the metal is known as an electric current, and it enables aluminum to conduct electricity.
Aluminum’s conductivity is so good that it is often used as a substitute for copper in electrical transmission lines. Although copper is the best conductor of electricity, it is denser and more expensive than aluminum. Using aluminum as a conductor enables electrical engineers to achieve the same level of conductivity at a lower cost.
Why Does Aluminum Conduct Electricity?
As noted above, the conductivity of aluminum is primarily due to the presence of free electrons within the metal. This, in turn, is determined by the atomic structure of aluminum.
Aluminum has 13 electrons arranged in three levels around its nucleus. The first two levels contain two electrons each, while the third level contains nine electrons. Of these nine electrons, only three are available for bonding with other atoms. The remaining six electrons are said to be free, or unbound. Because aluminum has relatively few valence electrons, they are easily excited out of the outermost energy level by a small voltage. This is why aluminum is such a good conductor of electricity.
The presence of free electrons in aluminum stems from the fact that aluminum’s valence electrons exist in what is known as a “sp-shell.” This means that the valence electrons are not very strongly bound to the atom, and can move freely within the metal. These free electrons are known as conduction electrons and they are responsible for conducting electricity through the metal.
Applications of Aluminum in the Electrical Industry
The excellent conductivity of aluminum, along with its other advantageous properties, makes it a popular choice in the electrical industry. Some key applications of aluminum in electrical systems include:
- Electrical Transmission Lines: Aluminum is often used for overhead power cables and transmission lines. It offers an efficient and cost-effective alternative to copper, as it can carry large amounts of electrical current over long distances without significant power loss. Additionally, aluminum is lighter in weight, making the installation and maintenance of transmission lines easier and more economical.
- Wiring and Electrical Connectors: Aluminum is also used in electrical wiring systems, especially in commercial and industrial buildings. It is commonly found in building service entrances, switchgear, and circuit breakers. Aluminum conductors are lightweight, flexible, and easy to handle, making them suitable for a variety of electrical applications.
- Heat Sink and Heat Transfer Systems: Aluminum’s high thermal conductivity makes it an excellent choice for heat sink and heat transfer systems in electrical components, such as power transistors and processors. The ability of aluminum to draw heat away from these components helps to prevent overheating and ensures the efficient operation of electronic devices.
- Capacitors and Electrical Conductors: Aluminum electrolytic capacitors are widely used in electronic devices, including power supplies, audio equipment, and automotive systems. Aluminum’s ability to conduct electricity allows it to store and discharge electrical energy in these capacitors. Additionally, aluminum is used as a coating on electrical conductors, providing them with protection against corrosion and enhancing their electrical performance.
- Aluminum Foils and Busbars: Aluminum foils are used as conductive elements in batteries, such as lithium-ion batteries, due to their high electrical conductivity and lightweight nature. Aluminum busbars, which are flat strips or bars of aluminum, are also commonly used in electrical equipment for distributing power safely and efficiently.
Frequently Asked Questions
Yes, aluminum does conduct electricity.
Aluminum conducts electricity due to the presence of free electrons in its atomic structure. These free electrons can move through the metal lattice, creating an electric current.
Aluminum is a relatively good conductor of electricity, although it is not as efficient as metals like copper.
Aluminum has a crystalline structure with a closely packed arrangement of atoms. This structure allows electrons to move freely through the lattice, contributing to its conductivity.
Aluminum has three valence electrons per atom. These electrons are loosely held and can move freely within the lattice when a voltage is applied, facilitating the flow of electric current.
While aluminum is not the best conductor of electricity, it still has good conductivity. It is not as conductive as copper but is used widely due to its lower cost and lighter weight.
Conclusion: Does Aluminum Conduct Electricity?
Aluminum is a versatile metal that conducts electricity. The conductivity of aluminum can be attributed to the presence of free electrons that conduct electrical current. This property makes aluminum a popular choice for its use in different electrical applications. Overall, the conductivity of aluminum is a testament to the fascinating and dynamic nature of the element, and it will likely continue to be a valuable resource for a range of industries in the years to come.
