aluminium corrosion

[chemfish]

Hi everyone. I have what might or might not be a problem and was wondering if anyone has any opinions. I recently bought a new quintrex dory hull and have used it a few times on sydney harbour. I have noticed the hull is no longer shiny and has started to develop a chalky/ dusty layer that looks like dried salt, I tried washing it off, and the chalkiness goes, but the hull still has those markings where the chalkiness was. Is this something to be worried about? Is it corrosion of some sort?

[bean]

I believe the metal has oxidised. Aluminium oxidises very quick when exposed to air/water and the white chalk powder is the result of the chemical reaction. If you were to polish the hull it will remove the white spots but there's hardly any point as it will return. I don't think you have too much too worry about.

Edited February 13, 2012 by bean

[brickman]

as said above aluminium is allways going to do this don;t polish it off just a wash down with water if you remove the oxidisation your removeing the protective layer if you keep doing it you will slowly reduce the thickness off the hull cheers gary

[mrbroadbill]

Try using anodes that will help to

[BWV]

That’s what it is suppose to do, the oxidation is how it protects itself. I know it doesn't look the best. If you do choose to polish it, its the start of a never ending job.

[chemfish]

thanks heaps everybody. i thought as much but had to make sure