The corrosion resistance of 0.5 mm thick aluminum coils depends on the specific alloy used in making the coils. Different aluminum alloys exhibit varying levels of corrosion resistance due to their elemental composition and the presence of protective surface treatments.

Generally speaking, aluminum is known for its excellent corrosion resistance, mainly due to the formation of a thin transparent oxide layer on its surface. This oxide layer (mainly aluminum oxide) provides a protective barrier that helps prevent further corrosion. However, specific corrosion resistance may vary depending on alloy and environmental conditions.

Common aluminum alloys and their general corrosion resistance include:

1xxx Series (e.g. 1100): These alloys are commercially pure aluminum and are highly corrosion resistant in most environments. However, they may not perform well in strongly acidic or alkaline conditions.

3xxx series (such as 3003): This series of alloys is not heat treatable and has good corrosion resistance. They are typically used in applications requiring moderate strength and corrosion resistance.

5xxx Series (e.g. 5052, 5083): These alloys are known for their high corrosion resistance, especially in marine environments. They also exhibit good formability and weldability.

6xxx series (e.g. 6061): This series of alloys is heat treatable and has good corrosion resistance. They are often used in structural applications.