Aluminium is a good conductor and is widely used in power transmission and distribution lines. It is lightweight, malleable, and ductile. Even more, it is available in abundance making it cheaper than other good conductors like copper, silver, and gold.
These properties of aluminium as a metal make it a good candidate for making winding wire. The aluminium winding wire technology has evolved rapidly making it a strong choice for a good number of applications.
Having said so, it will be wise to understand about aluminium winding wires before you choose them for your application. Here they are –
Points to consider while using Enamelled Aluminium Winding Wires-
1. Size of Aluminium Winding Wires
Aluminium is a good conductor. Yet it offers higher resistance to the electricity flow. Hence to get the same conductance, the size of the aluminium winding wire must be 25-30% more than copper winding wire of equivalent length.
This is because,
Resistivity of Copper at 20 °C is 1.68 x 10-8 Ohm
Resistivity of Aluminium at 20 °C 2.65 x 10-8 Ohm
The ratio of the resistance of Aluminium to Copper comes to (2.65 x 10-8) / (1.68 x 10-8) = 1.6
Or in other words, for the same application, the diameter of the aluminium winding wire or the number of turns must be much more than that when using a copper winding wire.
2. Making End Connections in Aluminium Winding Wire
The enamel must be removed and soldered or crimped to make end connections of winding wire.
Aluminium as a metal gets oxidised fast when exposed. And this oxide layer has an insulating nature. To make the terminal connections with aluminium winding wire, it needs to penetrate the oxide layer as well.
At the same time, the connection should be sealed airtight to prevent it from getting oxidised further. For this, high-pressure piercing crimp connectors are the most reliable.
However, for smaller sizes in aluminium winding wires (less than 32 SWG or 0.27mm) crimping is very difficult and leads to a lot of in-process rejection and rework. In this case, we can use self-solderable wires or special processes for soldering which are also accepted as reliable.
3. Corrosion Resistance
As a metal, aluminium is highly susceptible to corrosion. The oxide layer thus formed on the aluminium surface due to corrosion is an insulator.
In Aluminium winding wires, corrosion can thus reduce the effective inline diameter of the conductor. So, care should be taken to ensure that the insulating enamel layer over the conductor offers good corrosion resistance.
This makes aluminium winding wires less suitable for applications in damp or marine environments like submersible pumps.
4. Thermal Conductivity of Aluminium Winding Wires
The thermal conductivity of aluminium is less than that of copper. This makes Aluminium magnet wires susceptible to high hot spot temperatures, which can lead to shorter operating lives.
Aluminium has a higher thermal expansion coefficient and expands approximately one-third more than copper when put under heat. Be mindful of these thermal qualities of aluminium while checking suitability for your application.
5. Winding Speed
Aluminium winding wire offers high windability. Yet it has a weaker tensile strength making it brittle. Thus, operating on slightly slower winding speeds is recommended for Aluminium winding wires. Having the perfect understanding of handling and winding aluminium magnet wires can thus give you improved production efficiency.
6. Cost of Aluminium Winding Wires
As said earlier, the cost of aluminium is lower than copper – reducing your operating costs. Yet, cost advantage gets partly offset by lower winding speeds and a slight loss in operational efficiencies.
Also, since the diameter of the aluminium wire to be used is around 30% more, the consumption is approximately half of the copper and not 1/3rd which is sometimes expected due to the 1/3rd density of aluminium vis-à-vis copper.
7. Customer Satisfaction
Using aluminium winding wire can reduce the weight of your product making handling them easy for consumers. And definitely, the cost advantage can be passed on to the consumer making it a win-win deal.
It is very much possible to match the power performance of a motor wound with aluminium wire to one wound with copper wire. Since aluminium winding wire technology is relatively new, its usage is growing rapidly and more businesses are choosing them over copper wires.
Using Enamelled Aluminium Winding Wires
Aluminium winding wires are the perfect fit for applications where efficiency and volume are not benchmarks. For example, when motors need to work occasionally or for a short period – like in the case of some home appliances like a food processor or mixer grinder. [Read More: Growing Use of Aluminium Winding Wires in Home Appliances]
They are also suited for low-weight and larger-diameter applications like large motors and transformers in industrial applications.
The quality of aluminium winding wire can impact the life and performance of the application. Hence it is ideal to go for a winding wire manufacturer following strict quality protocols.
GEEKAY Winding is an established copper and aluminium winding wire manufacturer. We have a strong customer support team who can guide you with best winding practices for aluminium winding wire. Our technical R&D team has the expertise to customise aluminium winding wire to match all technical specifications that can increase the brand value of your product.
Check out our aluminium winding wire range and contact us with your specifications for a sample.