aluminium alone corrodes especially when exposed to salt water.
aluminum alloys, in which aluminum is the principal metal, come in grades, from 1000 series through 9000 series.
most tent poles made from 6000 or 7000 series aluminum alloys
aluminum is anodized to make it more resistant to corrosion and this process used to require nitric and phosphoric acid in the polishing stage but now DAC have invented Green Anodizing process to avid toxic chemical usage.
they are also given a temper grade:
6000 series alloys are a blend of aluminum, magnesium, silicon and other trace elements
the alloy 6061 is widely utilized in yacht, aircraft and bicycle manufacturing, but it is also commonly used for tent poles
this alloy is strong and resistant to corrosion, even if scratched
7000 series aluminum alloys are a blend of aluminum, zinc and other trace elements
this combination gives the highest strength of any aluminum alloy
7001 has the highest yield strength (the point at which a pole becomes permanently bent) and is frequently used in tent poles, and it has the added benefit of having good corrosion resistance.