Identifying Ti

[Osbourn]

As I've mentioned on occasion, I get a lot of unidentified materials. I have some 1/4" square bar stock, around 10 feet long. I have several of these. They're a dull grey color, and non-magnetic. I assumed that they were some construction grade of stainless, and put some to use based on that. I made on into a stirrer for melting Al, one piece was an aerator for the garden, etc. The stirrer was forged. I heated it up to around 2000f, and it still only gave up its single bend very grudgingly. I cut it with an angle grinder because the bandsaw just notched it. Could this actually be titanium that I've been so carelessly tossing around? I was under the impression that such low heats wouldn't affect the maleability of Ti at all, but I don't KNOW that to be the case. What could I do to ID it for sure? Spark test? It already doesn't etch. What properties should I look for?

------------------
Oz

"Sticking feathers up your butt does not make you a chicken!"
http://www.freespeech.org/oz/

 

[L6steel]

Try grinding some. The only ti I've ground on shoots brite white sparks and stinks something fierce.

------------------
Take care!! Michael

Always think of your fellow knife makers as partners in the search for the perfect blade, not as people trying to compete with you and your work!
http://www.nebsnow.com/L6steel
Buzzards gotta eat, same as worms!!!

 

[Nakano 2]

Leave a piece of it submersed in a highly concentrated solution of salt water?

Nakano

 

[EricElson]

Oz
If you grind it and it streams bright white sparks its probobly Ti,
After that your guess is as good as mine for what alloy etc. it could be...

L8R
Eric

http://www.elsonknives.tsx.org

 

[GrantP]

Oz,

Do you have a weight scale handy? You could measure off a chunk, figure its volume and then weigh it.

Pure Ti is about 4.5 g/cm^3 (0.163 lb./in.^3). If you come up close to this value, it's almost certainly Ti or a Ti-alloy as just about everything else is significantly lighter (Al, Mg...) or heavier (Fe, Ni, Cu...).

Some other physical properties of pure Ti can be found here:
http://www.webelements.com/webelements/elements/text/Ti/phys.html

I like the graphic of how a polished Ti goblet should appear. Very cute.

But I digress.

As for which alloy if it is Ti? Odds are it would be Ti-6Al-4V or commerically pure as those are the most common. I'm not sure if Ti alloys can be told apart by spark testing (I'm guessing probably not).

Hope this helps,
Grant