Does treating metal reduce the effects of weathering in a California climate?

Does treating metal reduce the effects of weathering in a California climate? This experiment deals with the elements of weather against metal; wind, rain, solar radiation, oxidation (uniting a substance with oxygen), and heat (the presence and absence of). My hypothesis is that the painted protected metal will fare better than the bare metal during the weathering. The reason I believe this will happen is that the protected metal has that extra layer, so it …

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