3. The thermal expansion coefficient of aluminum alloy is much higher than that of copper, AA8030 aluminum alloy is even higher than the aluminum alloy
|10X6/℃||Cu||Al||Al alloyAA1000||Al alloyAA1350||Al alloyAA8030|
As can be seen from the table, the thermal expansion coefficient of aluminum is much higher than that of copper, aluminum alloy AA1000 and AA1350 have some improvement, while AA8030 is even higher than aluminum. High thermal expansion coefficient causes the conductor to be exposed to undesirable and vicious cycle after thermal expansion and contraction, and the power supply has always been in peak valley, which has been a great test for cable performance.
4. Aluminum alloy does not solve the aluminum oxidation problem
Aluminum or aluminum exposure in the atmosphere will quickly form a hard, strong bond but fragile, about 10 nm, the thickness of the film has high resistivity, its hardness and cohesive force makes it difficult to form a conductive contact, this is aluminum and aluminum alloy before installation must remove the cause of the surface oxide layer. The copper surface is also oxidized, but the oxide layer is soft and it is easy to break into a semiconductor when the force is in force, forming metal-metal contact.