On Sat, 10 May 2008 08:17:16 -0700 (PDT), "
wrote:

On May 9, 8:04 pm, "Ed Huntress" wrote:

Not that I know of, Dan. Titanium has a reputation for not work-hardening
very much. It's worth checking out, in the machining context, but I'm pretty
sure that's the situation in general.

Titanium can be miserable to machine -- I remember doing some machining of
it back in the mid-'70s -- but my recollection is that it was more tough and
gummy than hard. But that's pretty far back in memory for me.

--
Ed Huntress

Hmmm. I did a little looking on the internet and found sites that
said Titanium work hardens about like 1020 steel, that is not a lot.
But they followed this with warnings not to do anything that would
work harden it. Possibly more because it will gall and also because
it does not conduct heat well. So it sounds as if you can't harden
titanium much by work hardening, you need to machine it as if it does
work harden.

Dan

At one point I did some work on the SR-71's which had titanium skin. I
have no idea what alloy it was but it seemed similar to stainless
except that it work hardened even worse. It seemed like if the drill
slipped for one revolution the stuff became uncutable. We used a lot
of carbide drill bits in the short time we supported them.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)