Electrical conductors are materials that allow electric current to flow through them with minimal resistance. In other words, they have high electrical conductivity. Conductors are usually metals, such as copper, silver, gold, and aluminum, but they can also include some non-metals, such as graphite. The electrons in conductive materials are able to move freely, allowing electric current to pass through the material with ease. This property makes conductors useful in many electrical applications, such as wiring, circuits, and electronic devices.
Why are overhead power lines made of aluminum?
Overhead power lines are often made of aluminum instead of copper or other materials for several reasons:
- Lightweight: Aluminum is a lighter metal than copper, which makes it easier and more cost-effective to transport and install.
- Cost-effective: Aluminum is less expensive than copper, making it a more cost-effective material for large-scale applications like power transmission.
- Corrosion-resistant: Aluminum is naturally resistant to corrosion, which means it can withstand exposure to the elements and last longer than other metals.
- High conductivity: Although aluminum has lower conductivity than copper, it still has a relatively high conductivity compared to other metals. This means that it can still efficiently conduct electricity, making it suitable for use in power lines.
Overall, aluminum’s combination of lightweight, cost-effectiveness, corrosion-resistance, and conductivity makes it an ideal material for overhead power lines.
There are several different aluminum alloys that can be used for overhead power lines, but the most common alloy used is 1350-H19. This alloy has a high purity level and is specifically designed for electrical applications, with a minimum conductivity of 61.8% IACS (International Annealed Copper Standard).
The “1350” in the alloy designation indicates that the aluminum has a minimum purity level of 99.5%, while the “H19” designation refers to the temper or hardness of the material. H19 is a relatively hard temper that provides a good balance of strength and ductility, making it suitable for use in overhead power lines.
Other aluminum alloys that can be used for overhead power lines include 6201-T81 and 6101-T81, which have higher strength and conductivity levels than 1350-H19 but are also more expensive. The specific alloy used will depend on the specific requirements of the power transmission system and the cost considerations of the project.