Why can't copper wire and 1 Series Alloy Aluminum Wire be co

Jul 14, 2023

Advantages and disadvantages of copper and aluminum wires:

Same area

Copper wire is more loaded than aluminum wire.
Copper wire is more flexible than aluminum wire.
Copper wire has a lower resistivity than aluminum wire.
Copper wire is more stable than aluminum wire.
However, the copper wire is about 3.5 times the price of the aluminum wire!
Why can't copper wire and 1 Series Alloy Aluminum Wire be connected?



(copper aluminum wire connector)
The chemical and physical properties of copper and aluminum are very large and should not be directly connected.
However, copper-aluminum connections are inevitable.
When connection is required, copper-aluminum transition clamps, copper-aluminum transition joints, copper wire tin-silica or aluminum wire tin-tin are generally used for direct connection.

Because the electrochemical properties of the two metals, copper and aluminum, are different.
If they are directly connected, a chemical battery is formed when water, carbon dioxide and other impurities are formed in the electrolyte.
This is because aluminum tends to lose electrons and become a negative electrode. It is difficult for copper to lose electrons to become a positive electrode. Thus, an electromotive force of 1.69V is formed between the positive and negative electrodes, and a small current is passed through to corrode the aluminum wire, so-called electrification. corrosion.
This will cause poor contact between copper and aluminum and increase the contact resistance.

When there is current, it will increase the temperature of the joint, and the temperature will increase and accelerate the corrosion of the joint, increasing the contact resistance, causing a vicious cycle until it burns and even causes a fire.