Salt air is brutal on building materials. Here is the materials-science reason aluminium handles it where timber and steel struggle.
The marine zone problem
Within a few hundred metres of surf, salt-laden air corrodes steel, breaks down timber oils and accelerates the greying and rot of natural wood. Materials that are fine inland fail fast by the sea.
How aluminium behaves
Aluminium forms a thin, self-renewing oxide layer that protects the metal beneath, so it does not rust the way steel does. Marine-grade alloys are chosen specifically for this corrosion resistance.
The practical upshot
A woodgrain aluminium facade, screen or fence keeps performing in the salt air where a timber one greys within a season and a steel one needs its coating watched carefully. A periodic fresh-water rinse is all it asks.