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Clear type II anodize over masked black type III anodize
November 18, 2016
Q. I've got a design in my head that I think works, but I'm wondering if there are any gotchas
Treatment &
Finishing of
Aluminium and
Its Alloys"
by Wernick, Pinner
& Sheasby
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Processing looks like this:
-Part is aluminum 6061
-Mask is applied (contains two separate traces)
-Type III anodization is performed (leaving raw aluminum where masked)
-Type II anodization is performed to give corrosion resistance to the raw aluminum areas
End result would be a black aluminum part with 2 clear traces (from the mask) that are conductive themselves but insulated from each other.
Also I wonder if, instead of masking, I hardcoat the whole thing, hit it with a laser, and then type ii coat it.
Does anyone see any issues (obvious or potential) with either approach (masking or laser)?
product designer - Brookline, Massachusetts, US
A. Chris
Your two-step coating can be done. The two stripes may be conductive but they are not insulated. The oxide layer formed as a result of a secondary laser operation will likely cause challenges for applying Type II coating. Type III anodize followed by machining, or mask / Type III / unmask will be less troublesome.
- Green Mountain Falls, Colorado
November 22, 2016
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