Anodizing different alloys

[TONYZ]

Just getting started with anodizing and achieved good success with the sample pieces done so far. The samples were small lengths of aluminium angle from the scrap bin. The nature of the profile leads me to think they would probably be a 6000 series alloy.

However on attempting to anodize the pieces I have turned up out of bar stock that I know is 2011 alloy, I find that the process is not proceeding in the same way at all.

The sample pieces did not bubble during anodizing, but a good anodised coating was developed that accepted dye color and rubs up to an excellent glossy finish.

The 2011 alloy pieces bubble strongly with many fine bubbles during anodizing. The anodizing coating is built up (i.e. the surface becomes non-conductive) but the initially polished surface becomes dull and only accepts a tint of color. It does not dye up with the deep intense color of the 6000 series samples even though I have used the same dye bath (food dye).

I won'd detail my entire process here for brevity, but I can reliably get good anodizing with the 6000 series samples, so I must have the technique more or less on the right track.

1. Is the difference due to the different composition of the alloys?

2. Is a good dyeable surface possible with 2011 alloy?

3. Which part of my process most likely needs modification to get 2011 alloy anodizing and coloring well?

[mcaswell]

Yes, the difference is likely due to the different alloys. Look at page 143 in the manual.

Sure, you should be able to anodize this alloy.

You'll likely need to modify the power you are using. See page 144 in the manual.

For more detailed product support questions, please use our PRS system at http://www.caswellplating.com/support.htm

[jnbsystems]

Yes, the difference is likely due to the different alloys. Look at page 143 in the manual.

Mike, my manual has something different on that page, something about gold plating. Do I have a different book? It's got a yellow cover on it, if that makes any difference. I received it with my LCD Anodizing kit about 6 weeks ago.

No big deal, just wondering, I wanted to make sure I have the latest book

THANKS!