Tuesday, September 28, 2021

Aluminum Wire, An Alternative To Copper Electrical Conductors.


A wire is any wire mainly made of iron, copper, brass, silver, or aluminum. The building wire process is performed by stretching the metals, as mentioned earlier. This phenomenon occurs thanks to their ductility property, which allows the different metals to deform without breaking.

There are wires with different thicknesses since there is no exact limit defined. However, as a curiosity, it is worth mentioning that it is called a rod when the wire is very thin.

Among its main characteristics is its capacity to be wound in coils of different lengths, facilitating its transportation. Another of its most significant features is its flexibility without the risk of breakage. This allows its malleability and favors its installation.

On the other hand, wire is a conductive material. As it transmits electricity so efficiently, it has an infinite number of uses today, such as its use in fiber optic installations. But this is not its only application; the wire is also used as a standard telephone carrier, for cable television, for industrial automation.

In our daily life, we also have a lot of wire in our everyday life, as you can see in construction, in roads and bridges, or horticulture. Depending on the building wire material, it usually has one use or another.

Non-magnetic metals such as tin, copper, aluminum, silver, or copper are considered ideal conductors of electricity. The building wire industry uses a wide selection of metallic conductors, but the most common are those using aluminum or copper. The main properties required of these conductors are conductivity, tensile strength, weight, and price.

Although copper has a more extended and older history as the material of choice for electrical conductivity, aluminum has certain advantages that make it more attractive for some specific applications. For example, aluminum has only 60% of the conductivity of copper but only 30% of its weight. That means that a bare aluminum cable weighs half as much as a copper cable with the same electrical resistance. This, together with the fact that its price per unit weight is a third of copper, explains why aluminum is often the material of choice for medium-sized cross-sections.

Aluminum conductors are composed of different alloys known as the AA-1350 and AA-8000 series. The AA-1350 series has a minimum aluminum content of 99.5%.

 Aluminum has a very high reactive capacity and is a slightly oxidizing material. Therefore, when an electrically conductive liquid affects an aluminum-copper connection, an electrochemical reaction occurs, resulting in the formation of the contact element. In this process, the potential differences produced to play a decisive role as the contact element is formed with copper electrodes (anodes), electrolytes (water), and aluminum electrodes (cathodes).

The voltage generated short-circuits the copper and aluminum contact. An accumulation or decomposition of the aluminum occurs according to the outgoing current flow. This process is visible, forms an increasing oxidation zone, and displays dust particles located on the aluminum in minor parts and even as a permanent reaction because the copper does not decompose. The transient resistance increases in an electrical connection, leading to a temperature rise, and in the worst case, to a fire.

In response, aluminum alloys were improved to have creep and elongation properties more similar to copper, but great care must always be taken with these types of connections. In addition, connectors must be rated for use with aluminum.