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Required time to build up titanium oxide layer?

July 30, 2009

Hi there,

I'm working as a co-op mechanical engineering student at an automation company. We are trying to use titanium heat tips for a soldering application. During cycling the heat tips are cleaned using garnet paper. We are trying to establish how long it takes to build up an oxide layer on the titanium heat tips. Currently we heat the tips to 400 °C for five minutes, however this value seems arbitrary. Can anyone point me in the right direction towards finding information about this? In terms of measuring the formation of oxide, is it possible to pass a fixed electrical current through the tip and measure the voltage to determine the work function of the material?

Thanks,

Will

Will Zochodne
Co-Op Student - Waterloo, Ontario, Canada

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March 13, 2010

Hi, Will. Most of the world's knowledge is empirical and I see nothing second-class about empiric knowledge. Titanium is a very active material and will always build an oxide layer -- but how thick will depend on time, temperature, humidity, and other environmental factors. If you determine that the layer formed in five minutes at 400 °C is sufficient, that's great. It might be easier and more revealing to test 2-1/2 minutes and 10 minutes than to study other people's results for different alloys under different conditions

But one thing that may help you quantify the situation quickly is that titanium builds a transparent oxidation layer that creates a diffraction pattern where the apparent color of the article can tell you how thick the oxidation layer is. Search for "coloring titanium", or review letters 7926, 937, 1265 and others to see how to build this oxidation layer with electricity and mild acids. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey