Copper Mountain Mining Corporation T.CUM

Drawbacks of aluminum wire

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Aluminum wire has a lot of drawbacks.  Here are a few:

1. Aluminum does not conduct as well as copper, so you have to use a thicker wire.  Aluminum conductivity is 61% of what copper is.

2. When the outer layer of copper oxidizes (tarnishes), it is still conductive.  Aluminum oxide is an insulator.

3. Aluminum is difficult to solder.

4. Aluminum is relatively soft, and as temperature increases, expands more than the metals from which connectors are made. When current flows through a connection, the connection becomes warmer. The expansion of the aluminum, confined under a screw terminal, generates tremendous pressure, so that the metal “flows” into the empty spaces in the connector. When the electrical load is removed, the aluminum cools and contracts, and a gap forms between the wire and the connector. The slightly loose-fitting connection now has a higher resistance, and more corrosion forms in the gap, further increasing the resistance. 

5. Aluminum will fatigue and break down more readily when subjected to bending and other forms of abuse than copper, which is more ductile. 

There are methods to overcome some of these problems, but suffice it to say that aluminum cannot be simply substituted for copper.  The product would need to be redesigned, and manufacturing process would need to be changed.