Why Iron (Fe) corrodes and Aluminium (Al) doesn't?

Ahh!!! But aluminum does. Aluminum corrodes faster than does iron. It is nearly impossible to have a piece of aluminum that does not have a thin coating of aluminum oxide on it. The catch is that the layer of Al2O3 on aluminum metal is "passivating". That means that the layer prevents any more aluminum than just the surface atoms from reacting, this protecting it from further corrosion. It is also possible to make iron so that a passivating layer forms on the surface.