Aluminium for seawater 2

[tkwricky]

We need some aluminium material to fabricate a seawater inlet for foilcat. so we choose AL5083/5052

Chemical Composition for:
Si/Fe/Cu/Mn/Mg/Cr/Zn/Ti
AL5083 0.4-0.7/0.4/0.1/0.4-1/4-4.9/0.05-0.25/0.25/0.15
AL5052 0.25/0.4/0.1/0.1/2.2-2.8/0.15-0.35/0.1/-

Now we broguht some aluminium from China the result is:
Si/0.034 Fe/0.18 Cu/0.003 Mn/0.036 Mg/2.9 Cr/0.26 Zn/0.006 Ti/0.007

What is this? the material is good for use? good for welding? still have a good saltwater corrosion protection.

 

[rnd2]

5083 Al plate is used for hulls. It is easier to form curves than 60XX series.
The chinese alloy is low in copper. That is good if used for seawater application.
Mg is the only other metal that is more than a trace and that is also found in alloy 5356. It is a common aluminium welding alloy and used for welding 5083.

 

[EdStainless]

Check the microstructure and hav some samples tested in seawater. If hte microstructure is dirty or heavily banded you might have very poor sw corrosion resistance.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm