Aluminum explanations

[SEBASTIANOFA]

Hello everyone, I ask for some clarifications on aluminum from those who can help me.
First info: let's assume a painted aluminum surface that is scratched in a small spot with a non-humid climate, if it were steel we would see rust over time, but being aluminum will it protect itself even if the rest of the surface is painted?

Second info: let's assume a motorcycle aluminum alloy frame, will the imperfections / impurities of the metal itself inevitably create corrosion? The only way to stop corrosion in these areas is to isolate them from oxygen or, once the imperfection is exhausted, will they go to passivate themselves again, stopping the process?

Third info: what is the best way to degrease bare aluminum in addition to neutral soap? Isopropyl alcohol? White spirit?
Thanks guys

 

[NorthCivil]

aluminium does corrode. though it does not corrode like steel.

when aluminium corrodes, the oxidized atoms form a thin protective surface at the outer layer.

https://www.metalswarehouse.co.uk/does-aluminium-rust/

 

[WKTaylor]

S... straight talk to you...

This website cannot train You to understand aluminum-alloy fundamentals... There are plenty of books/publications/classes/etc for 'learning'.

We can only provide professional insights into topics that 'You have some fundamental understanding/orientation in/about'. It is obvious You need to know a lot more basics, before our advice would be make sense and be useful.

Regards, Wil Taylor
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