Cliff wrote:

On Sat, 28 Jan 2006 17:56:55 -0500, Wade Berlin
wrote:

however, I
think the phrase is "Mettalic", not metal. Carbon is a non-metal,
Tungston is a metal, and the resulting alloy is metallic, not a metal.

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================== ======
Alloy:

Substance composed of two or more metals. Alloys, like pure metals,
possess metallic luster and conduct heat and electricity well, although
not generally as well as do the pure metals of which they are formed.
Compounds that contain both a metal or metals and certain nonmetals,
particularly those containing carbon, are also called alloys. The most
important of these is steel.
An alloy may consist of an intermetallic compound, a solid solution,
an intimate mixture of minute crystals of the constituent metallic
elements, or any combination of solutions or mixtures of the foregoing.

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.


"Alloy," Microsoft® Encarta® Encyclopedia 2000. © 1993-1999 Microsoft
Corporation. All rights reserved.
================================================== ======


From Physics Daily:
================================================== ======
http://www.physicsdaily.com/physics/Tungsten_carbide

Tungsten carbide

Tungsten carbide, WC or W2C, is an alloy of tungsten and carbon similar
to titanium carbide. Its extreme hardness makes it useful in the
manufacture of cutting tools, abrasives and bearings, as a cheaper
alternative to diamond.

Alloy

An alloy is a combination, either in solution or compound, of two or
more elements, at least one of which is a metal, and where the resultant
material has metallic properties.
================================================== ======


--
BottleBob
http://home.earthlink.net/~bottlbob

On Sun, 29 Jan 2006 22:49:37 GMT, BottleBob wrote:

Cliff wrote:

On Sat, 28 Jan 2006 17:56:55 -0500, Wade Berlin
wrote:

however, I
think the phrase is "Mettalic", not metal. Carbon is a non-metal,
Tungston is a metal, and the resulting alloy is metallic, not a metal.

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================= =======
Alloy:

Substance composed of two or more metals.

Reading issues again: Carbon is not usually a metal.
Now, about Hydrogen Carbide ....
HTH
--
Cliff

Cliff wrote:

On Sun, 29 Jan 2006 22:49:37 GMT, BottleBob wrote:

Cliff wrote:

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================= =======
Alloy:

Substance composed of two or more metals.

So Carbon is a metal per your lint?


Cliff:

Of course not. And you know very well that the excerpt from Encarta
said no such thing. You've again creatively edited out the context to
make it "appear" that something was said which really wasn't. You even
intentionally removed the complete original excerpt to make a comparison
with the full context more difficult. Here is the complete original
alloy excerpt I posted:

================================================== =========
From Encarta Encyclopedia.

Alloy:

Substance composed of two or more metals. Alloys, like pure
metals,
possess metallic luster and conduct heat and electricity well, although
not generally as well as do the pure metals of which they are formed.
Compounds that contain both a metal or metals and certain nonmetals,
particularly those containing carbon, are also called alloys. The most
important of these is steel.
An alloy may consist of an intermetallic compound, a solid
solution,
an intimate mixture of minute crystals of the constituent metallic
elements, or any combination of solutions or mixtures of the foregoing.
================================================== ===========

Please note where it says: "Compounds that contain both a metal or
metals and certain nonmetals, particularly those containing carbon, are
also called alloys." Which contradicts the implication you were trying
to make (that the article was stating that carbon was a metal), by you
posting a sentence out of context.

Do you really think such misleading tactics are considered an honest
search for the truth? If someone can't be trusted to tell the truth in
a matter so inconsequential as a definition of alloy, then how can they
be trusted to tell the truth in matters much more serious and important?

This is just a little feeback 'ol buddy, but IMO, you should rethink
your habit of engaging in this sort of self-serving
maneuvering/misrepresentation, since it's not exactly improving your
credibility.


--
BottleBob
http://home.earthlink.net/~bottlbob

On Mon, 30 Jan 2006 15:20:28 GMT, BottleBob wrote:

Cliff wrote:

On Sun, 29 Jan 2006 22:49:37 GMT, BottleBob wrote:

Cliff wrote:

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================= =======
Alloy:

Substance composed of two or more metals.

So Carbon is a metal per your lint?


Cliff:

Of course not.

So your statement "Depends on who you ask." is false?

And you know very well that the excerpt from Encarta
said no such thing.

I must have missed the
[
Alloy:
Substance composed of two or more metals.
]
bits G.

You've again creatively edited out the context to
make it "appear" that something was said which really wasn't.

So it did NOT say
[
Alloy:
Substance composed of two or more metals.
]
??

You even
intentionally removed the complete original excerpt to make a comparison
with the full context more difficult. Here is the complete original
alloy excerpt I posted:

================================================= ==========
From Encarta Encyclopedia.

Alloy:

Substance composed of two or more metals.

DANG !!! THERE IT IS AGAIN !!

Alloys, like pure
metals,
possess metallic luster and conduct heat and electricity well, although
not generally as well as do the pure metals of which they are formed.

How aout that?

Compounds that contain both a metal or metals and certain nonmetals,
particularly those containing carbon, are also called alloys. The most
important of these is steel.

So is Hydrogen Carbide a metal?

An alloy may consist of an intermetallic compound, a solid
solution,
an intimate mixture of minute crystals of the constituent metallic
elements, or any combination of solutions or mixtures of the foregoing.

And that applies to sintered (Cobalt & other binders) Carbides how?

================================================= ============

Please note where it says: "Compounds that contain both a metal or
metals and certain nonmetals, particularly those containing carbon, are
also called alloys." Which contradicts the implication you were trying
to make (that the article was stating that carbon was a metal), by you
posting a sentence out of context.

Their context ...

Do you really think such misleading tactics are considered an honest
search for the truth?

Tungsten Carbide is not a metal it seems G.

If someone can't be trusted to tell the truth in
a matter so inconsequential as a definition of alloy,

NOW you think it's an alloy?

then how can they
be trusted to tell the truth in matters much more serious and important?

Like words, eh?

This is just a little feeback 'ol buddy, but IMO, you should rethink
your habit of engaging in this sort of self-serving
maneuvering/misrepresentation, since it's not exactly improving your
credibility.

Your lint lost it's way long ago, BB G.
--
Cliff

BottleBob wrote:
This is just a little feeback 'ol buddy, but IMO, you should rethink
your habit of engaging in this sort of self-serving
maneuvering/misrepresentation, since it's not exactly improving your
credibility.

With respect to Cliff:

He has lost his credibility a LOOOOONG time ago. :-)
...lew...

On Mon, 30 Jan 2006 23:18:37 GMT, Lew Hartswick
wrote:

BottleBob wrote:
This is just a little feeback 'ol buddy, but IMO, you should rethink
your habit of engaging in this sort of self-serving
maneuvering/misrepresentation, since it's not exactly improving your
credibility.

With respect to Cliff:

He has lost his credibility a LOOOOONG time ago. :-)

Was this about glass again G?
Or Tungsten Carbide being a metal?

LOL ....
--
Cliff

Cliff wrote:

On Mon, 30 Jan 2006 15:20:28 GMT, BottleBob wrote:

Cliff wrote:

On Sun, 29 Jan 2006 22:49:37 GMT, BottleBob wrote:

Cliff wrote:

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================= =======
Alloy:

Substance composed of two or more metals.

So Carbon is a metal per your lint?


Cliff:

Of course not.

So your statement "Depends on who you ask." is false?

Cliff:

Huh? That was a response to your original assertion that "Tungsten
carbide is not an alloy."


And you know very well that the excerpt from Encarta
said no such thing.

I must have missed the
[
Alloy:
Substance composed of two or more metals.
]
bits G.

Here's the contextual bit from the Encarta excerpt you seem to keep
missing:
"Compounds that contain both a metal or metals and certain nonmetals,
particularly those containing carbon, are also called alloys. The most
important of these is steel."

Besides, is a substance composed of two or more metal an alloy, or not?

Bottom line is that you took something out of context to make it appear
that something was said that wasn't. Now you're trying to defend that
action by continuing to ignore the context? LOL

Quit wasting my time with your silly trolling word games.

--
BottleBob
http://home.earthlink.net/~bottlbob

On Wed, 01 Feb 2006 18:07:21 GMT, BottleBob wrote:

Cliff wrote:

On Mon, 30 Jan 2006 15:20:28 GMT, BottleBob wrote:

Cliff wrote:

On Sun, 29 Jan 2006 22:49:37 GMT, BottleBob wrote:

Cliff wrote:

But Tungsten Carbide is not an alloy.


Cliff:

Depends on who you ask.

From Encarta Encyclopedia:
================================================= =======
Alloy:

Substance composed of two or more metals.

So Carbon is a metal per your lint?


Cliff:

Of course not.

So your statement "Depends on who you ask." is false?

Cliff:

Huh? That was a response to your original assertion that "Tungsten
carbide is not an alloy."

It's not, anymore than table salt or Hydrogen Carbide are.
Your lint's opine is, as usual, useless and well off track again.


And you know very well that the excerpt from Encarta
said no such thing.

I must have missed the
[
Alloy:
Substance composed of two or more metals.
]
bits G.

Here's the contextual bit from the Encarta excerpt you seem to keep
missing:
"Compounds that contain both a metal or metals and certain nonmetals,
particularly those containing carbon, are also called alloys. The most
important of these is steel."

Besides, is a substance composed of two or more metal an alloy, or not?

Often. But probably not always G.

Bottom line is that you took something out of context to make it appear
that something was said that wasn't. Now you're trying to defend that
action by continuing to ignore the context? LOL

Quit wasting my time with your silly trolling word games.

Words have meanings.
Bait is where you find it too G.
Are alloys rocks?
--
Cliff

Cliff wrote:

On Wed, 01 Feb 2006 18:07:21 GMT, BottleBob wrote:


Quit wasting my time with your silly trolling word games.


Bait is where you find it too G.


I think that just about says it all.


--
BottleBob
http://home.earthlink.net/~bottlbob

Newsgroups: alt.machines.cnc,rec.crafts.metalworking...

I was wondering where this mess came from.

Just got done with a metallurgy class and WC is not an alloy it's
a compound. When looking at binary Phase Diagrams the straight
verticle lines are compounds.

But Tungsten Carbide is not an alloy.

Right.

The tool-material, "Tungsten Carbide" is like a composite material.
The manufacturing of WC tools resembles a ceramic material.

From Encarta Encyclopedia:
================================================= =======
Alloy:
Substance composed of two or more metals.

Ooops.

The E.E. wasn't written by metallurgists huh?

Alvin in AZ

wrote:

Newsgroups: alt.machines.cnc,rec.crafts.metalworking...

I was wondering where this mess came from.

Just got done with a metallurgy class and WC is not an alloy it's
a compound. When looking at binary Phase Diagrams the straight
verticle lines are compounds.

Alvin:

Ahh but we're not talking about just WC, but WC with a cobalt binder to
make "Carbide" tooling.


But Tungsten Carbide is not an alloy.

Right.

Again, it seems to depend on who you ask.

Here's an interesting excerpt from your own metallurgy newsgroup.

================================================== ==========
1. Dr Alun J. Carr

Newsgroups: sci.engr.metallurgy
From: (Dr Alun J. Carr)
Subject: Can someone tell me what WC is?


Richard Larker wrote:

On the other hand, the name for the metal matrix composite WC-Co used by
the latter languages, "Hardmetals", is also misleading since the metal
content is small (often below 10%) and contributes to the toughness, not
the hardness! The name Cemented (or Sintered) Carbide is a far better name
for a category of materials composed of Hard (ceramic) + (tough) metal.

Again, 'hardmetal' comes from the German. The hard phase was known by
the
Germans as 'hartstoffe' and the sintered material, with metallic binder,
as
'hartmetalle'. According to Scwarzkopf & Kieffer (Schwarzkopf, P. &
Kieffer, R. (1953) Refractory Hard Metals, New York: Macmillan):

In English -- at least in a number of American and English
publications,
including this book -- the term "hard metals" is used for the
binder-free substances as well as for the cemented materials. In
view of
the physical properties, particularly the electrical
conductivity which
clearly indicates metallic bonding, the use of the term for
binder-free
substances also appears justified.

In English, we would also refer to the hard phase as an 'Interstitial
Alloy' (Goldschmidt, H. J. (1967) Interstitial Alloys, London:
Butterworth), because it is _not_ a ceramic. WC, TiC, ZrC, TiN, etc. are
all brittle solids, with hardnesses similar to ceramics, but unlike
ceramics, the interatomic bonding is predominantly _metallic_ (evidenced
by, amongst other things, the high electrical conductivity (see above),
and
the metallic lustre). To quote Schwarzkopf & Kieffer again (ibid):

The term "hard metals" is used to specify a group of
high-melting hard
substances which have metallic character although, on the basis
of
chemical composition, they would be considered inorganic
compounds.
Typical representatives of these materials are the refractory
carbides
of the transition metals of the fourth to sixth groups of the
periodic
system, such as, particularly, the carbides of tungsten,
titanium, and
tantalum.

It is therefore incorrect to refer to cemented carbides as 'cermets', as
they contain no ceramic. To do so is a sign of intellectual laziness
(unfortunately common in the hard materials community today -- I do not
intend to attack Dr Larker personally: I feel he has been misinformed),
merely classifying all hard substances as 'ceramics', merely because
they
are 'hard', when one should instead consider the nature of the
interatomic
bond as the basis for a system of classification.


Alun

--
Dr Alun J. CARR Phone: +353-1-7061989
Mechanical Engineering Dept. +353-1-2693244 x1989
University College Dublin Fax: +353-1-2830534
Belfield
Dublin 4 http://tizit.ucd.ie/ajcarr/
Ireland
================================================== ==========



The tool-material, "Tungsten Carbide" is like a composite material.
The manufacturing of WC tools resembles a ceramic material.

From Encarta Encyclopedia:
================================================= =======
Alloy:
Substance composed of two or more metals.

Ooops.

The E.E. wasn't written by metallurgists huh?

They certainly could have expressed the first sentence better. But the
rest of the excerpt seems cogent.

================================================== =============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================== ==============


--
BottleBob
http://home.earthlink.net/~bottlbob

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

wrote:

Newsgroups: alt.machines.cnc,rec.crafts.metalworking...

I was wondering where this mess came from.

Just got done with a metallurgy class and WC is not an alloy it's
a compound. When looking at binary Phase Diagrams the straight
verticle lines are compounds.

Alvin:

Ahh but we're not talking about just WC, but WC with a cobalt binder to
make "Carbide" tooling.


But Tungsten Carbide is not an alloy.

Right.

Again, it seems to depend on who you ask.

Here's an interesting excerpt from your own metallurgy newsgroup.

================================================= ===========
1. Dr Alun J. Carr

Newsgroups: sci.engr.metallurgy
From: (Dr Alun J. Carr)
Subject: Can someone tell me what WC is?


Richard Larker wrote:

On the other hand, the name for the metal matrix composite WC-Co used by
the latter languages, "Hardmetals", is also misleading since the metal
content is small (often below 10%) and contributes to the toughness, not
the hardness! The name Cemented (or Sintered) Carbide is a far better name
for a category of materials composed of Hard (ceramic) + (tough) metal.

Again, 'hardmetal' comes from the German. The hard phase was known by
the
Germans as 'hartstoffe' and the sintered material, with metallic binder,
as
'hartmetalle'. According to Scwarzkopf & Kieffer (Schwarzkopf, P. &
Kieffer, R. (1953) Refractory Hard Metals, New York: Macmillan):

In English -- at least in a number of American and English
publications,
including this book -- the term "hard metals" is used for the
binder-free substances as well as for the cemented materials. In
view of
the physical properties, particularly the electrical
conductivity which
clearly indicates metallic bonding, the use of the term for
binder-free
substances also appears justified.

In English, we would also refer to the hard phase as an 'Interstitial
Alloy' (Goldschmidt, H. J. (1967) Interstitial Alloys, London:
Butterworth), because it is _not_ a ceramic. WC, TiC, ZrC, TiN, etc. are
all brittle solids, with hardnesses similar to ceramics, but unlike
ceramics, the interatomic bonding is predominantly _metallic_ (evidenced
by, amongst other things, the high electrical conductivity (see above),
and
the metallic lustre). To quote Schwarzkopf & Kieffer again (ibid):

The term "hard metals" is used to specify a group of
high-melting hard
substances which have metallic character although, on the basis
of
chemical composition, they would be considered inorganic
compounds.
Typical representatives of these materials are the refractory
carbides
of the transition metals of the fourth to sixth groups of the
periodic
system, such as, particularly, the carbides of tungsten,
titanium, and
tantalum.

It is therefore incorrect to refer to cemented carbides as 'cermets', as
they contain no ceramic. To do so is a sign of intellectual laziness
(unfortunately common in the hard materials community today -- I do not
intend to attack Dr Larker personally: I feel he has been misinformed),
merely classifying all hard substances as 'ceramics', merely because
they
are 'hard', when one should instead consider the nature of the
interatomic
bond as the basis for a system of classification.


Alun

--
Dr Alun J. CARR Phone: +353-1-7061989
Mechanical Engineering Dept. +353-1-2693244 x1989
University College Dublin Fax: +353-1-2830534
Belfield
Dublin 4 http://tizit.ucd.ie/ajcarr/
Ireland
================================================= ===========



The tool-material, "Tungsten Carbide" is like a composite material.
The manufacturing of WC tools resembles a ceramic material.

From Encarta Encyclopedia:
================================================= =======
Alloy:
Substance composed of two or more metals.

Ooops.

The E.E. wasn't written by metallurgists huh?

They certainly could have expressed the first sentence better. But the
rest of the excerpt seems cogent.

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

[
In a tragic 1945 criticality accident, Harry K. Daghlian, Jr. dropped a brick of
tungsten carbide (which is a neutron reflector) onto a plutonium core, causing
it to reach critical mass. He died a month later, of radiation poisoning.
]
--
Cliff

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

Again, it seems to depend on who you ask.

Quasicrystals are metal alloys but ...
[
Though they are composed of excellent electrical conductors such as aluminum and
copper, quasicrystalline alloys themselves are extremely resistive -- the more
perfect the quasicrystal, the more resistive it becomes.
]
http://www.lbl.gov/Science-Articles/...al-states.html
--
Cliff

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

Again, it seems to depend on who you ask.

Quasicrystals are metal alloys but ...
[
Though they are composed of excellent electrical conductors such as aluminum and
copper, quasicrystalline alloys themselves are extremely resistive -- the more
perfect the quasicrystal, the more resistive it becomes.
]
http://www.lbl.gov/Science-Articles/...al-states.html

Cliff:

================================================== ========
....Max-Planck Society, Berlin, and their colleagues investigated the
electronic structure of a quasicrystalline alloy of
aluminum-nickel-cobalt (AlNiCo) by means of angle-resolved
photoemission.
================================================== ========

Interesting, but exactly what do these aluminum-nickel-cobalt
quasicrystals have to do with the properties of tungsten carbide
tooling? Are you trying to make a parallel that both quasicrystals and
tungsten-carbon-cobalt are alloys?

--
BottleBob
http://home.earthlink.net/~bottlbob

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

Cliff:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, a mutually exclusive terms.


--
BottleBob
http://home.earthlink.net/~bottlbob

On Thu, 02 Feb 2006 13:23:59 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

Again, it seems to depend on who you ask.

Quasicrystals are metal alloys but ...
[
Though they are composed of excellent electrical conductors such as aluminum and
copper, quasicrystalline alloys themselves are extremely resistive -- the more
perfect the quasicrystal, the more resistive it becomes.
]
http://www.lbl.gov/Science-Articles/...al-states.html

Cliff:

================================================= =========
...Max-Planck Society, Berlin, and their colleagues investigated the
electronic structure of a quasicrystalline alloy of
aluminum-nickel-cobalt (AlNiCo) by means of angle-resolved
photoemission.
================================================= =========

Interesting, but exactly what do these aluminum-nickel-cobalt
quasicrystals have to do with the properties of tungsten carbide
tooling? Are you trying to make a parallel that both quasicrystals and
tungsten-carbon-cobalt are alloys?

You were trying to claim that as Tungsten was a metal then WC was
as well at one point.
Later you seemed to be claiming that metal Carbides were metals (I
asked about Hydrogen Carbide too G).
Then that things made of a mixture of metals in an "alloy" were metals
(which these quasicrystals [this was just one example of such])
were metals and quasicrystals are seemingly in doubt G.

What about conductive plastics? Do you think that they are metals too?
Then there was the rock confusion. Is a block of steel a rock?

Why is a duck?

BTW, When you want to post of Cobalt (or other binders) sintered
Carbide(s) tooling RATHER than Tungsten Carbide I think you've
got a ceramic again G.
--
Cliff

On Thu, 02 Feb 2006 13:27:13 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

Cliff:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, a mutually exclusive terms.

??
How could a cermet be other than a cermet?
BTW, is not a "cermet" a subset of the more general "ceramic"?
As in "All cermets are ceramics but not all ceramics are cermets"?

BB, Remember those posts on the logical flaws that you like? Had
two or three links IIRC ....
--
Cliff

Cliff wrote:

On Thu, 02 Feb 2006 13:27:13 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

Cliff:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, a mutually exclusive terms.

??
How could a cermet be other than a cermet?

Cliff:

Sorry, I left out a part of my sentence. It should have read:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, AND ALLOY are mutually exclusive terms.


--
BottleBob
http://home.earthlink.net/~bottlbob

On Thu, 02 Feb 2006 22:59:34 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 13:27:13 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

Cliff:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, a mutually exclusive terms.

??
How could a cermet be other than a cermet?

Cliff:

Sorry, I left out a part of my sentence. It should have read:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, AND ALLOY are mutually exclusive terms.

And that changes what?
You think that low-alloy Steel is a ceramic now?
--
Cliff

Cliff wrote:



You were trying to claim that as Tungsten was a metal then WC was
as well at one point.

Cliff:

Actually I believe it was "Carbide Tooling" made up of Tungsten carbide
& a Cobalt binder that I was referring to, which is as yet, unresolved
to my satisfaction since they retain the free electrons of metals, and
therefore share the properties of metals.
Here's a tid-bit on Carbides, note the last section on WC:

================================================== ============
http://chemed.chem.purdue.edu/genche...n.php#carbides

Carbides: Covalent, Ionic, and Interstitial

Although carbon is essentially inert at room temperature, it reacts with
less electronegative negative elements at high temperatures to form
compounds known as carbides. When carbon reacts with an element of
similar size and electronegativity, a covalent carbide is produced.
Silicon carbide, for example, is made by treating silicon dioxide from
quartz with an excess of carbon in an electric furnace at 2300 K.
SiO2(s) + 3 C(s) SiC(s) + 2 CO(g)

Covalent carbides have properties similar to those of diamond. Both SiC
and diamond are inert to chemical reactions, except at very high
temperatures; both have very high melting points; and both are among the
hardest substances known. SiC was first synthesized by Edward Acheson in
1891. Shortly thereafter, Acheson founded the Carborundum Company to
market this material. Then, as now, materials in this class are most
commonly used as abrasives.

Compounds that contain carbon and one of the more active metals are
called ionic carbides.
CaO(s) + 3 C(s) CaC2(s) + CO(g)

It is useful to think about these compounds as if they contained
negatively charged carbon ions: [Ca2+][C22-] or [Al3+]4[C4-]3. This
model is useful because it explains why these carbides burst into flame
when added to water. The ionic carbides that formally contain the C4-
ion react with water to form methane, which is ignited by the heat given
off in this reaction.
C4- + 4 H2O CH4 + 4 OH-

The ionic carbides that formally contain the C22- ion react with water
to form acetylene, which is ignited by the heat of reaction.
C22- + 2 H2O C2H2 + 2 OH-

At one time, miners' lamps were fueled by the combustion of acetylene
prepared from the reaction of calcium carbide with water.

Interstitial carbides, such as tungsten carbide (WC), form when carbon
combines with a metal that has an intermediate electronegativity and a
relatively large atomic radius. In these compounds, the carbon atoms
pack in the holes (interstices) between planes of metal atoms. The
interstitial carbides, which include TiC, ZrC, and MoC retain the
properties of metals. They act as alloys, rather than as either salts or
covalent compounds.
================================================== ============

Later you seemed to be claiming that metal Carbides were metals...

See the above section on Interstitial carbides which retain the
properties of metals as opposed to ionic and covalently bonded carbides
that are generally non conductive.


Then that things made of a mixture of metals in an "alloy" were metals
(which these quasicrystals [this was just one example of such])
were metals and quasicrystals are seemingly in doubt G.

The term "alloy" is not always defined in a consistent manner. Some
definitions would include the intimate mixing of powders in powder
metallurgy, some don't.


BTW, When you want to post of Cobalt (or other binders) sintered
Carbide(s) tooling RATHER than Tungsten Carbide I think you've
got a ceramic again G.

Ceramic is another term that seems to be limited in consistently
addressing all the structural varieties & combinations of materials
considered "ceramic", IMO.

================================================== ===========
http://www.ndt-ed.org/EducationResou...re/ceramic.htm

Ceramic Structures

The two most common chemical bonds for ceramic materials are covalent
and ionic. The bonding of atoms together is much stronger in covalent
and ionic bonding than in metallic. This is why ceramics generally have
the following properties: high hardness, high compressive strength, and
chemical inertness. This strong bonding also accounts for the less
attractive properties of ceramics, such as low ductility and low tensile
strength. The absence of free electrons is responsible for making most
ceramics poor conductors of electricity and heat.

However, it should be noted that the crystal structures of ceramics are
many and varied and this results in a very wide range of properties. For
example, while ceramics are perceived as electrical and thermal
insulators, ceramic oxide (initially based on Y-Ba-Cu-O) is the basis
for high temperature superconductivity. Diamond and silicon carbide have
a higher thermal conductivity than aluminum or copper.
================================================== ===========

--
BottleBob
http://home.earthlink.net/~bottlbob

Cliff wrote:

On Thu, 02 Feb 2006 22:59:34 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 13:27:13 GMT, BottleBob wrote:

Cliff wrote:

On Thu, 02 Feb 2006 05:32:53 GMT, BottleBob wrote:

================================================= ==============
From Encarta:

Historically, most alloys have been prepared by mixing the molten
materials. More recently, powder metallurgy has become important in the
preparation of alloys with special characteristics. In this process, the
alloys are prepared by mixing dry powders of the materials, squeezing
them together under high pressure, and then heating them to temperatures
just below their melting points. The result is a solid, homogeneous
alloy.
Among the alloys made possible by powder metallurgy are the
cermets.
These alloys of metal and carbon (carbides), boron (borides), oxygen
(oxides), silicon (silicides), and nitrogen (nitrides) combine the
advantages of the high-temperature strength, stability, and oxidation
resistance of the ceramic compound with the ductility and shock
resistance of the metal.
================================================= ===============

The "CRC Materials Science and Engineering Handbook" seems to think it's (WC)
a ceramic too.

Cliff:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, a mutually exclusive terms.

??
How could a cermet be other than a cermet?

Cliff:

Sorry, I left out a part of my sentence. It should have read:

You seem to be functioning under the impression that ceramic, or more
correctly cermet, AND ALLOY are mutually exclusive terms.

And that changes what?

Cliff:

I posted an Encarta definition of alloy that included the process of
powder metallurgy. You responded with a reference to the "CRC Materials
Science and Engineering Handbook", but didn't list what they said OR an
address to check exactly what they said, just that they think WC is a
ceramic. I responded with the observation that you seem to think that
the term ceramic and alloy are mutually exclusive. Do you?

You think that low-alloy Steel is a ceramic now?

Silly nonsense remarks neither adds support to your position nor makes
you appear particularly objective. Either you have something
intelligent to contribute related to the subject matter at hand, or you
don't.


--
BottleBob
http://home.earthlink.net/~bottlbob

On Sat, 04 Feb 2006 13:42:02 GMT, BottleBob wrote:

Cliff wrote:



You were trying to claim that as Tungsten was a metal then WC was
as well at one point.

Cliff:

Actually I believe it was "Carbide Tooling" made up of Tungsten carbide
& a Cobalt binder that I was referring to,

Not what was explicitly originally posted on which I commented and
to which you objected.

which is as yet, unresolved
to my satisfaction

How about your lint's?

since they retain the free electrons of metals, and
therefore share the properties of metals.

Well, naturally the COBALT is a metal.
Or were you thinking of conductiuve plastics & suchlike?

Here's a tid-bit on Carbides, note the last section on WC:

================================================= =============
http://chemed.chem.purdue.edu/genche...n.php#carbides

Carbides: Covalent, Ionic, and Interstitial

Which is Hydrogen Carbide?

Although carbon is essentially inert at room temperature, it reacts with
less electronegative negative elements at high temperatures to form
compounds known as carbides. When carbon reacts with an element of
similar size and electronegativity, a covalent carbide is produced.
Silicon carbide, for example, is made by treating silicon dioxide from
quartz with an excess of carbon in an electric furnace at 2300 K.
SiO2(s) + 3 C(s) SiC(s) + 2 CO(g)

Covalent carbides have properties similar to those of diamond. Both SiC
and diamond are inert to chemical reactions, except at very high
temperatures; both have very high melting points; and both are among the
hardest substances known. SiC was first synthesized by Edward Acheson in
1891. Shortly thereafter, Acheson founded the Carborundum Company to
market this material. Then, as now, materials in this class are most
commonly used as abrasives.

Compounds that contain carbon and one of the more active metals are
called ionic carbides.
CaO(s) + 3 C(s) CaC2(s) + CO(g)

Hydrogen is pretty "active", right?

It is useful to think about these compounds as if they contained
negatively charged carbon ions: [Ca2+][C22-] or [Al3+]4[C4-]3. This
model is useful because it explains why these carbides burst into flame
when added to water. The ionic carbides that formally contain the C4-
ion react with water to form methane, which is ignited by the heat given
off in this reaction.
C4- + 4 H2O CH4 + 4 OH-


I thought Calcium Carbide produced acetylene.

The ionic carbides that formally contain the C22- ion react with water
to form acetylene, which is ignited by the heat of reaction.
C22- + 2 H2O C2H2 + 2 OH-

Yep.

At one time, miners' lamps were fueled by the combustion of acetylene
prepared from the reaction of calcium carbide with water.

I've long known about such. Carbide cannons too.

Interstitial carbides, such as tungsten carbide (WC), form when carbon
combines with a metal that has an intermediate electronegativity and a
relatively large atomic radius. In these compounds, the carbon atoms
pack in the holes (interstices) between planes of metal atoms. The
interstitial carbides, which include TiC, ZrC, and MoC retain the
properties of metals. They act as alloys, rather than as either salts or
covalent compounds.
================================================= =============

Later you seemed to be claiming that metal Carbides were metals...

See the above section on Interstitial carbides which retain the
properties of metals as opposed to ionic and covalently bonded carbides
that are generally non conductive.


Then that things made of a mixture of metals in an "alloy" were metals
(which these quasicrystals [this was just one example of such])
were metals and quasicrystals are seemingly in doubt G.

The term "alloy" is not always defined in a consistent manner. Some
definitions would include the intimate mixing of powders in powder
metallurgy, some don't.


BTW, When you want to post of Cobalt (or other binders) sintered
Carbide(s) tooling RATHER than Tungsten Carbide I think you've
got a ceramic again G.

Ceramic is another term that seems to be limited in consistently
addressing all the structural varieties & combinations of materials
considered "ceramic", IMO.

================================================= ============
http://www.ndt-ed.org/EducationResou...re/ceramic.htm

Ceramic Structures

The two most common chemical bonds for ceramic materials are covalent
and ionic. The bonding of atoms together is much stronger in covalent
and ionic bonding than in metallic. This is why ceramics generally have
the following properties: high hardness, high compressive strength, and
chemical inertness. This strong bonding also accounts for the less
attractive properties of ceramics, such as low ductility and low tensile
strength. The absence of free electrons is responsible for making most
ceramics poor conductors of electricity and heat.

However, it should be noted that the crystal structures of ceramics are
many and varied and this results in a very wide range of properties. For
example, while ceramics are perceived as electrical and thermal
insulators, ceramic oxide (initially based on Y-Ba-Cu-O) is the basis
for high temperature superconductivity. Diamond and silicon carbide have
a higher thermal conductivity than aluminum or copper.
================================================= ============
--
Cliff

On Sat, 04 Feb 2006 13:55:11 GMT, BottleBob wrote:

Cliff:

I posted an Encarta definition of alloy that included the process of
powder metallurgy. You responded with a reference to the "CRC Materials
Science and Engineering Handbook", but didn't list what they said OR an
address to check exactly what they said, just that they think WC is a
ceramic.

So it would seem.

I responded with the observation that you seem to think that
the term ceramic and alloy are mutually exclusive. Do you?

You think that low-alloy Steel is a ceramic now?

Silly nonsense remarks neither adds support to your position nor makes
you appear particularly objective. Either you have something
intelligent to contribute related to the subject matter at hand, or you
don't.

I'm not the guy with the "could be" lint to help me out G.
--
Cliff