Re: [PSUBS-MAILIST] protecting aluminum parts

["Adam Lawrence" <adteleka@in-tch.com>]

Oxygen accelerates corrosion attack, and the corrosion rate goes into orbit
under higher atmospheric pressures. Polishing the part would have removed
the passive oxide film at the surface, giving the oxidizing agent (sea
water) a fresh start. 316 has higher Ni and Mo making it a better choice
then 304.

Adam


----- Original Message ----- 
From: <VBra676539@aol.com>

> Hmmm. Maybe one of our metal guys will take a shot at that. The only thing
I
> ever did similar was replace a piece of 304 stainless in the oxygen system
on
> one of the boats when it turned to rust on a single dive. It should have
been
> 316 to start with, but we were all surprised that it rusted like that. I
> wonder if we could have polished it out and by doing so, sealed the pores
and maybe
> made it shinier and less likely to do it again? Very strange. Vance