Comment by numpad0
12 hours ago
> Why the dye? I thought anodising's colour comes only from the voltage used, with no dye needed.
That's true for anodization processes for some other metals like titanium and stainless steel, but aluminum is dyed. Also the process is material specific. Anodization for Al is only possible because Al does that unique self organizing micropore thing.
Yep, you're right. I was thinking of titanium. :)
If anyone's interested in details of Aluminium anodising, this seems like a decently thorough introduction: https://nzic.org.nz/unsecure_files/book/8E.pdf