Why Can’t Copper and Aluminum Wires Be Connected Directly?
Copper and aluminum have significantly different electrochemical properties.
When joined, the presence of even minimal moisture or airborne salts creates a galvanic cell—essentially a tiny battery—at the connection point.
Aluminum, being more reactive, acts as the anode and corrodes rapidly, turning into a powdery oxide.
The joint weakens, contact resistance increases, and overheating begins.










