Titanium Anodization

What is it?

It is a thin layer of titanium oxide that as it thickens, will change the wavelength of light refracted. Like a thin hardened crystalizedlayer, it is chemically bonded to the titanium and will wear off over time. Remember titanium is a hard and tough material so it will not wear easily. The anodization is actually harder than the base metal and will help to protect the part.

How is titanium anodized?

There are two main ways to form the titanium oxide layer on titanium. Before you attempt to try them yourself you need to understand the risks and take the necessary precautions to keep yourself safe. The most popular and easier to control is through electrolysis, the other using heat. Electrolysis is a little more involved and requires a few chemicals but also you need a power supply that has a variable voltage output and needs to output at least 1 or more amps. By adjusting the voltage from 5v to 120v you can achieve different oxide thicknesses and therefore different colors. The use of heat can also be employed and is a very cost effective means. You need a way to hold the part(and not get burned) and source of heat(blow torch). You can also control the process more using a heat treating oven and achieve a more uniform oxide layer. The use of a blow torch has it’s inherent risks and is more difficult to achieve a specific color. Also heat anodizing limits the range of colors you can achieve. You’ll mostly find bronze, blue and purples using a torch.

As an alternative to an expensive power supply I've seen many people use 9v batteries connected in series to achieve different voltages but again this limits you to voltages in multiples of 9.

A clean part is very important! You must remove any impurities like dirt and oil and the surface needs to be the desired texture. Attempting to finish the part after anodization will remove the oxide layer and scrap the part. As a tip you’ll also want to etch the part after it’s cleaned and degreased. Etching the part will give you a much more uniform and professional finish.

If you are wanting to take on anodizing your titanium parts please be careful. Make sure there are no other metals like steel, brass, nickel etc as part of the piece you are anodizing. It will affect the finish and in some cases ruin to piece. Refer to the many YouTube tutorials for all the different ways you can achieve these colors yourself.