Chrome plating an anodized aluminum or titanium surface

A. Hi, Amy. Yes, it is possible to electroplate onto phosphoric acid anodized aluminum, and there is probably no reason that chrome can't be the topmost layer of that plating. Plating with good adhesion onto titanium is very difficult and I'm not personally aware of the possibility of plating onto anodized titanium.

Unfortunately though, while highly specific questions are often answerable, the more general ones like yours tend to be tougher because there are always a hundred ifs, ands, and buts -- the fact that I believe the general proposition is theoretically possible doesn't mean your application will work :-)

Please give us some details of what you are trying to do and we should be able to offer specific instructions and encouragement or discouragement. Thanks!

A. The only anodizing that is electroplated to my knowledge is phosphoric acid anodizing, and it is so thin that I don't think it will take dyes that will offer a saturated color anything like what you're looking for. I could be wrong, but I don't think it is possible to electroplate the sulfuric acid anodizing that we associate with bright colors. Secondly, chrome plating isn't transparent or translucent, so the color will not show through. Third, I don't think you would be able to chrome plate directly onto anodizing, but would need an intermediate plating layer like nickel which also would not be transparent :-)

Why do you want to chrome plate this item?

Okay, sorry for the misunderstanding. You want to chrome plate the colored anodizing, but only need to see the color if the plating isn't there (presumably in selective areas where the plating hasn't been applied, or where it has worn away). Sorry, I am still don't understand enough of what you want to do to be much help, and realize that you can't tell us too much because it's proprietary. But good luck.

A. Amy,

Phosphoric acid anodizing does not take dyes and it produces dull grey anodic coating on aluminum surface. Therefore, PAA cannot meet your requirement. Titanium anodizing itself can produce bright colors.

Both anodized aluminum and titanium can be further plated in terms of proprietary processes, including final chrome finish. For the same reason that you cannot disclose your application, the proprietary processes for plating anodized aluminum cannot be disclosed here. But this does not prevent you from developing your own processes. It can be done for sure. Good luck!

A. My approach would be to PVD coat the surface. We regularly deposit coatings with different colors, and often layer them. It would be very easy to apply a specific color, say gold, on the surface, then apply a silvery coating on top of it. Both coatings would be much harder than chrome (our coatings have Rc near 90), far more wear resistant. Titanium would be the preferred substrate.