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Combining Titanium and Carbon

I am a student in partnership with my uncle in formulating ideas about different things. One day he passed me a question about combining Titanium and Carbon (both dust forms), the end product would be to make the titanium stronger and lighter, but the problem is that the valent circles on both types of molecules don't match up. I was wondering if when we combine the titanium and the carbon (under pressure and heat) can we bathe the mixture in a gas or add another metal that would not greatly affect the process yet still help with the bonding? Thanks for time and answer,

Caleb Hawkins
student - Bremerton, Washington, USA
2003

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First of two simultaneous responses --

What you want to do is to make titanium carbide, which is readily formed by titanium and carbon. In principle all you need to do is to heat the titanium and carbon to a pretty high temperature and you will get the carbide. However, before you start, and run the risk of killing yourselves and others by a huge explosion, go to the technical literature in your library and seek out the exact method

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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Second of two simultaneous responses -- 2003

Caleb,

I don't really understand what is meant by your comment that the "molecules don't match up". TiC, forming between 10 and 19.3 weight percent C, has a Pearson structure symbol of cF8, while Ti2C, containing between 10 and 12.4% C, has a Pearson structure symbol of cF48. Remember that they are ceramics, so the stoichiometry can vary.

Actually, I'm throwing the Pearson jargon at you to let you know that there has been a lot of work already done on these materials. Your question indicates to me that you haven't digested it. That's no problem, of course, but it means a little library time might save you a lot of time and expense. Find the C-Ti phase diagram, and if it doesn't make sense to you read the appropriate section of an introductory materials science text until it does. Then decide what it is you want to do with your project.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York

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2003

Ti and C do form stable alloys and compounds. C is soluble in Ti (similar to how sugar is soluble in water to make Kool-Aid) up to 0.2% by weight when Ti has a body-centered cubic crystal structure and up to 0.4% by weight when Ti has a face-centered cubic crystal structure. Beyond those limits, TiC or Ti₂C form, with TiC being the most stable form.

Toby Padfield
- Troy, MI USA