Aluminum is the most abundantly found element on the Earth’s surface. It is a silvery-white metal that is soft and bendable. Because of its malleable nature, it is used in aircraft and automobile production, as it can take pressure without breaking. The packers use it in food packing. Aluminum is used frequently in construction. Often aluminum is used to make windows and doors.
Aluminum is very similar to steel, brass, and copper in its physical, chemical, and mechanical composition. It is often melted, cast, and formed in much the same way as steel. It is light in weight, which makes it different from these metals. Because of this, it is used in construction because it effectively reduces cost prices.
You can adapt its different strengths by modifying its alloys. It is ductile, which means you can use it for wires and electronics.
Before we discuss aluminum as a conductor, let us discuss electricity conductors.
Anything that allows an easy flow of electricity through it is called an electricity conductor. When exposed to current, the loose electrons or ions in the conductor become the carriers and quickly carry the current from electron to electron. The free electrons are not attached to any atom or a covalent bond; they carry the electric charge, thus causing a chain effect, which is called current. Aluminum contains three such electrons that are not attached to any bond and carry electricity easily. When the energy source channelizes the electrons, they start moving from one end to the other, from the negative to the positive terminal of the source.
Aluminum is considered an excellent choice as a conductor of electricity which is why electricians use it in electronics. The electrical conductivity is 3.5 X 107 S/m at 20 °C. It is also used for the main power transmission lines. It ranks fourth in the metal conductivity list. Silver, Copper, and Gold are the top three. Silver and gold are not used because of being too expensive; hence aluminum is the most sensible choice because of its free flow. Copper is also used very often as a conductor, but the preference for aluminum is based on its weight. It is light and hence much more compatible.
Why is aluminum the most widely used metal as a conductor?
Surprisingly, it is not copper (which has eight free electrons for the perfect flow of current) that is the most widely used conductor, but aluminum. There are a few other properties that make aluminum a good choice.
1. Low Resistance
Resistance of a metal refers to its property of acting opposite to its conductance. Aluminum has a low resistance making it a very good conductor. Its electrical resistance can be measured as 2.82 X 10-8 Ω-m, which is very low for a metal.
2. Ductility
Aluminum has a low density and melting point, meaning you can mold it in almost any shape. You can use different aluminum alloys in different applications according to the need. Because of this property, aluminum can be molded in any form to form a good wire that would conduct electricity.
3. Strength at low temperature
The malleable and ductile nature of aluminum allows it to bend, and its strength helps it to maintain its shape without breaking. Unlike steel and other metals, aluminum can maintain its structure and not break at low temperatures. Steel goes brittle when exposed to a lower temperature. This property is important as a conductor for any metal.
4. Corrosion Resistant
It is hard for metals to resist corrosion when exposed to air and water, but aluminum is extremely corrosion-resistant. It produces a thin oxide coating which becomes its protective layer to save it from corrosion. This property is important for a good conductor. We cannot allow our wires to go rusty. Steel and iron are not used as conductors because they are highly prone to corrosion.
5. Non-Magnetic
If a conductor is magnetic, the wires will start sticking to each other, which is not a good scenario. aluminum is non-magnetic, making it a good conductor. This property makes it ideal for electrical shielings such as computer disks, dish antennas, or busbars.
6. Shock-Absorbent and Non-Sparking
Aluminum is extremely shock absorbing, making it another reason to use it abundantly. It is also non-sparking. It produces no spark when it comes in contact with itself or any ferrous object. This property is extremely useful as a conductor. When electricity passes through it, the metal mustn’t spark; otherwise, a short circuit will be dangerous. It is also shock-absorbant and used in heavy appliances without the fear of breaking or getting sparked.
Applications that Utilize Aluminum as An Electric Conductor
It has many applications as a conductor. It is used in the following:
- Utility Grids
Due to its weight and cost advantage, aluminum is the preferred choice as a conductor. It weighs half as much as copper and costs far less as well.
- Electrical wiring
Due to the better conductivity over weight ratio, it is preferred over copper wiring and is extensively used in residences, aircraft, buildings, and appliances.
- Electric Busbars
Electric busbars are used to distribute electricity to different circuits inside the buildings. Aluminum is chosen as the preferred choice because of its lightweight.
Impact Of Aluminum Finish on Electrical Conductivity
Conclusion
Aluminum is a good conductor of electricity owing to the sea of delocalized electrons present in it. Its conductivity is lower than copper, but because of its lightweight, engineers prefer it over copper. There are a whole lot of other properties as well. Its low resistance and non-sparking nature make it a good choice as a conductor. The corrosion resistance of aluminum makes it a good candidate for long-term conductors. The major properties that make aluminum a conductor are its low weight, low cost, low resistance, and corrosion resistance.