"BottleBob" wrote in message
...
Ed Huntress wrote:


I offered some information based on a lot of years in
that particular field. Take it or leave it as you wish.

Ed:

I indeed thank you for your input. I just happened to see
the term used quite frequently in my researches the last few
days.

--
BottleBob

Oh, damn, Bob, I have to apologize. My brain was thinking "heavy metal"
while my fingers were typing "hardmetal."

Let me try to straighten this out before I really confuse anybody who cares.
The tungsten alloy boring bars (and insert-type drill shanks, etc.) are
called "heavy metal," not "hardmetal." Those are the ones with the
properties I mentioned: very high stiffness and good damping. Tungsten
is...well, a very heavy metal, as well as being much stiffer than steel.

"Hardmetal" is an old slang term for various metal-matrix sintered carbides
(as Jim Rosin said, they're also called "cemented carbides," which is an
accurate description of what they are): tungsten carbide, tantalum carbide,
and chromium carbide (used in gage blocks) for the most part. It's an old
term that's been around since the first half of the last century, and it
does indeed refer to carbides.

My mistake. I'm sorry if I got anyone scratching their heads over this.
Brain fart. g

--
Ed Huntress