Anodizing Al vs Ti discussion

Hi @Jedillama, you are right that anodizing titanium is different from anodizing aluminum. In both cases, an oxide layer is formed, but with aluminum, that oxide layer is then used like a primer to hold a colour dye. Where as titanium (and niobium and tantallum) create clear oxide layers that alter light refraction and can create different colours based on the thickness of the oxide layer. Heating titanium with a torch has the same effect as electrolysis where the titanium atoms are excited and bond to oxygen atoms to form a titanium oxide crystal layer. However, electrolysis is much more precise and exact colours can be formed by running a specific voltage through the metal. It is more finicky to get the same vibrancy of colour out of titanium as with niobium, but here is a voltage scale that I use for my niobium jewelry work and an example of two different bracelet colours.
edit: This scale applies directly to titanium as well.


So to get that gold colour I would say that a 55 volt current would be right about there.

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