On Fri, 17 Feb 2012 19:03:28 -0600, Richard
wrote:

On 2/17/2012 4:54 PM, Lloyd E. Sponenburgh wrote:
fired this volley in news:4CA%q.1145
:
Can I heat it with an oxy-acetylene torch to do this easier? I know I
can't weld it, and I don't need to join it anyway--I just need to bend
the wire into round shapes with curves1-inch diameter.

I've not ever played with titanium before.... does it turn a different
color when it gets near melting point? If the surface of the wire
oxidizes and turns funny colors is okay, I just don't want it to go
totally-soft permanently.


I'd be willing to try it with a carburizing flame. Make _absolutely_
sure the flame is on the fuel-rich side, because oxygen is your enemy
with titanium. Err on the side of too rich; titanium melts at about
3500F, and even a rich O/A flame will exceed 4500F.

But be careful. I'm a pyrotechnician by trade. Titanium is the stuff we
use to make "silver" sparks. It will burn well in open air, and is a
bitch to put out. It throws sparks several feet as it burns.

Hot forming of titanium can be done between 900F and 1450F. I'd suspect
hotter is better with hand-forming. 1450 approaches a full cherry red.

It will oxidize heavily upon exposure to air, but the oxide can be
removed abrasively. At lower temperatures, the oxides can be quite
beautiful with a whole array of peacock colors displayed.

LLoyd




Didn't Lockheed figure out they needed to work titanium in an inert gas
atmosphere?

You must weld it in an inert atmosphere. It can be done in a chamber
but it can also be done, as I've seen the A.F. do it, by plugging
titanium ducting with a foam plug and sticking a hose from a second
argon regulator through the plug into the duct. That takes care of the
"back side" and a little higher argon flow to the torch takes care of
the front side.

We used to stainless ducting the same way :-)

--
Cheers,

John B.