General corrosion (Topic 11027)

Aluminium is protected by an oxide layer which is stable between pH 4 and 8,5, and under these conditions aluminium will only experience local corrosion attacks. Below pH 4 and above pH 8,5, thus in acidic or alkaline conditions the oxide layer be will dissolved and a general thickness reduction distributed over the total aluminium surface will be seen. This is called general corrosion and this will only be a problem for aluminium exposed to strong chemicals like acids or bases.

The corrosion rates under such conditions are so severe that a surface treatment like a high quality lacquering system is imperative.