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Cleaning titanium before coating

How can I make sure the Titanium substrate is clean enough for TiN COATING? Is there a specific cleaning method which will eliminate the possibility of any contamination for before it goes for coating?

Karthik Trichi
Materials Engineer - Miramar, Florida, USA
2007

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There is no one, sure way to clean parts; you have to know what the nature of the contaminates are and the environmental and cost restrictions. There may be other restrictions from specifications (like you can't etch the surface, for example). Give details of the problem and you might get details in the answer.

James Totter, CEF
- Tallahassee, Florida
2007

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2007

You can use many cleaning processes developed for steels. You cannot use hydrochloric and hydrofluoric acids. Alkalis mild or strong are safe.
You may have some oxide or nitride on the surface, if so a neutral (pH7-10) solution of 2-10% hydrogen peroxide will dissolve it. You can control the pH with a mixture of tetra sodium pyrophosphate and phosphoric acid. It takes several hours cold or under an hour hot. Note that the hydrogen peroxide decomposes quite quickly and you have to add more when necessary. I usually set it up and leave it overnight. Titanium is quite safe in this solution.
Nick Clatworthy

Nick Clatworthy
- Whitstable, Kent, UK