Both great dissertations. Thanks for another interesting discussion.

Tim (TOP-posting for brevity)

--
"That's for the courts to decide." - Homer Simpson
Website @ http://webpages.charter.net/dawill/tmoranwms

"Don Wilkins" wrote in message
...
On Sun, 08 Feb 2004 07:49:38 GMT, "Ed Huntress"
wrote:

,;"Don Wilkins" wrote in message
...
,; On Sat, 07 Feb 2004 17:58:50 GMT, "Ed Huntress"
,; wrote:
,;
,; ,;"Don Wilkins" wrote in message
,; ...
,; ,; On 6 Feb 2004 17:29:55 -0800,
,; ,; (benwoodward.com) wrote:
,; ,;
,; ,; ,;Thank you for your replies. TC is a ceramic then. I was
totally
,; ,; ,;unaware just how alien to steel tc is. I'm classifying it
under
,;'alien
,; ,; ,;technology successfully reverse engineered' and leaving it at
,;that.:-)
,; ,;
,; ,; I certainly would not classify WC as a ceramic.
,; ,;
,; ,;The you would certainly be wrong, Don. WC is a ceramic.
,;Tungsten-carbide
,; ,;tools are made of a powder-metallurgy composite of WC ceramic and
metal
,; ,;powders.
,;
,; Well I disagree WC is not a ceramic.
,;
,; Take a look at a dictionary definition.
,;
,;HOkay, sometimes I lose track of the confusion that's propagated about
this
,;material, and the common uses of the term "ceramic," as well as the
vague
,;terms used in metallurgy to describe WC and TaC, which are interstitial
,;carbides. On top of it all, the metalworking- and other industrial
fields
,;have added their own jargon. This is going to be one of my lengthy
,;dissertations, so I'll apologize in advance and warn off anyone who
doesn't
,;really give a damn. On the other hand, they may find this interesting,
,;because it's the result of research I did on the history of carbide
tools in
,;1977, plus years of exposure as Materials Editor of American Machinist,
and
,;more recently as Tooling Editor of Machining magazine. You won't see it
put
,;together quite this way anywhere else, I believe.

I am going to delete some of your material here in the interest of
length. Your discussion covers most of the vagueness of the term
"ceramic" and I doubt if we would have any disagreement if we had the
opportunity to spend a couple hours in a face to face discussion of
the topic.

I am a research chemist and spent the first 15 years of my career in
the metallurgy research laboratory of a large corporation. What the
hell it was the General Electric Research Laboratory. The second 18
years I was at the same facility and although still dealing with the
metallurgists and ceramists I also had to contend with a bunch of
organic chemists. Ceramics was my second major in a PH.D. program at
the University of Illinois.

We probably made more cemented carbides than any other company and at
the time I started we were in the midst of developing the production
of synthetic diamonds. None of cemented carbide research or the
synthetic diamond research was done in our Ceramics Laboratory.

Yes the term is vague, widely used and widely miss-used. The following
information on ceramics is blatantly copied in part from the
"Encyclopedia of Chemistry" edited by G.L.Clark a well-known chemist
and one of my U of I professors. Parts of the stuff below was authored
by A.I. Andrews head of the Ceramics Department at the U of I and one
of my committee members.

**An all-embracing definition is rather difficult because it includes
what appears by a cursory examination to cover widely diverse areas. A
recent committee of the American Ceramic Society defined ceramics to
include those industries which manufacture products by the action of
heat on raw materials, most of which are of an earthy nature, in which
the chemical element silicon together with its oxide and complex
compounds known as silicates occupy a predominant position.

They go on to say "It is much easier to understand the scope of the
ceramic industry by a consideration of specific products. It may be
divided into seven major areas:"

For brevity's sake the areas are listed here by title only without
expansion...Structural clay products, Whitewares, All varieties of
glass products, Porcelain enamel products, Refractories, Cemented
materials such as Portland cement, & Abrasive materials such as
alumina, silicon carbide. ***

Now I can see a quick Ah Hah from Ed but would hasten to point out
that although cemented WC certainly fits in some of those categories
it is not specifically mentioned in the definitions. In addition
Cermets, Refractorys, & Abrasives are covered separately in the
Encyclopedia.

My problem with calling WC a ceramic probably comes from the viewpoint
of a chemist tainted by a long association with a bevy of ceramists
and metallurgists. Here is my reservation in a nutshell...Would one
call the following compounds ceramics: iron carbide, aluminum carbide,
iron oxide, calcium oxide, calcium carbide, silicon dioxide,
molybdenum sulfide, etc. If it is a single compound I would be very
hesitant to call it a ceramic. So by my definition one needs two or
more compounds along with some interaction so as to not have a simple
mixture to get a ceramic. WC (to me) is a chemical compound (it is a
carbide) as is e.g. SiO2 an oxide and not a ceramic. Quartz might give
me some hemming and hawing as one could consider it a glass which sort
of puts it in the ceramic category.

Cemented carbides fall very nicely into the category of "Cermets"
which is from my point of view a better and more descriptive and well
recognized category.

If the question had been "cemented WC" I probably wouldn't have made
the same comment but when the topic was WC it created all sorts of
misgivings to let that go by as a ceramic. Actually I am crotchety
enough in my old age so I still consider cemented carbides as cermets
not ceramics but how one classifies them probably depends a great deal
on one's background.

To repeat... Ed's excellent dissertation is deleted for brevity. It
certainly exhibits why there are differences of opinions even by those
actively working in the field which I haven't done for almost 18 years
now.
,;

,;
,;'Sorry for the length. I didn't have time to write it shorter. g

No need to apologize. Your points are well taken,interesting, &
instructive.

Don