Is tungsten carbide ferrous?

I would think not. AFAIK, a metal needs to contain iron to be called ferrous. Hence the name ferrous, from the Latin for iron, ferrum.

Tungsten is the element W. Carbon is the element C.

Tungsten Carbide has the molecular formula WC.

Pure tungsten carbide contains no iron, and thus is non-ferrous.

Tungsten carbide items may be made from powdered tungsten carbide, subjected to heat and pressure to bind it together. Other powder metals are probably added to the WC to help it stick together.

Even if some iron powder was added, it probably isn't considered "ferrous".

So overall, I believe the answer would be 'no'.

Dave

Binders in this case often contain a large amount of cobalt. While cobalt is magnetic (this may be what the original poster was getting after?) it does not qualify the material as being ferrous.

Jim

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No

Mark Rand RTFM

How can it be magnetic and not be ferrous? Can it rust? Can it be welded to steel? Welded with steel? Also, if I quench harden 2016, why won't it cut carbide? Can tungsten carbide be quench hardened? Forged? I wonder.

It can be ferromagnetic. Like the word phosphorescence, which now has nearly nothing(?) to do with phosphorous (which has only a weak phosphorescent effect anyway).

Rust is a specific form of oxide, ferric (III) oxide, so it can only form where there's iron.

Same thing? I doubt it, due to brittleness and differences in expansion rate. But I wouldn't know.

Something can only be cut by something harder...obviously, carbide needs to be cut with something a *lot* harder than steel. Like say, diamond. Unless you reversed your statement, in which case, I don't know what the specs are on cutting 2016 (aluminum? steel?) with carbide.

No. As far as I know it's a brittle material and can only be formed by casting (since it melts upwards of 5200°F, um, ...no), sintering or abrasive means of material removal (grinding, etc.). Being a definite chemical (WC) I doubt it has different phases, so all a quench would do is crack it. It's brittle, remember?

Now... I'll let someone like Ed H. correct me ;)

Tim

-- "That's for the courts to decide." - Homer Simpson Website @

Many tungsten carbide formulations contain cobalt power, which is magnetic. Some tungsten carbide formulations (not, generally, ones used for cutting tools) contain iron powder.

Only if it contains iron powder.

Nope, unless you want to count exotic techniques such as electron-beam welding. You can't weld it at home. It can be brazed to steel very nicely, however.

I don't get the distinction.

Carbide runs around 10 points higher on the Rockwell C hardness scale than the hardest steel.

No.

Not really.

Maybe you need a better explanation of what the material is. Tungsten carbide is a ceramic; a compound of carbon and tungsten, WC. Like most engineering ceramics, it's harder than any steel. It won't melt at the temperatures you can achieve in a shop.

When they make a tool out of tungsten carbide, they start with a powder ground from tungsten carbide crystals. Then they add powders of various metals to serve as a binder. When the application involves high temperatures, as with cutting tools, those metal additions are usually high-melting-point metals plus some others that are needed to achieve good bonding. Nickel and cobalt are common ones. Other metals, such as iron, may be used for lower-temp applications, such as wear parts for process machinery that doesn't run hot.

The powders are compressed in a die and then sintered. Sintering involves heating the compressed form in an oven until the binders reach a temperature just below their liquid state. They bond to each other, and to the particles of WC, by diffusion bonding, rather than by liquid welding.

The result is a kind of pudding, like concrete, with WC particles as the aggregate and diffusion-bonded metal as the cement. The total mass has a hardness somewhat below that of pure WC but well above that of steel. Any heat-treatment done to the part would be based on the heat-treatment characteristics of the metal binders. And, unlike steel, they generally don't heat-harden.

Ed Huntress

Certain materials other than iron also have magnetic properties. Cobalt is an example.

Rust is by definition iron oxide, so no.

No. It can be brazed.

Gary

Ever stick a canadian nickel to a magnet?

Others have mentioned cobalt, but nickel is a more common metal which is attracted to a magnet.

American nickels aren't attracted to a magnet because it isn't a pure enough form of nickel. Canadian nickels/quarters are.

Dave

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.:-)

Umm, I would say not a ceramic. There are many different definitions of ceramic but I think the best description of things like WC or TC would be a "cemented carbide."

Cemented because it's the binder (typically cobalt) that cements the harder particles together.

The notion of sintering is actually pretty complicated - why does the density go up, and the porosity down, when a bunch of powder is heated?

Turns out that as the temperature goes up, the free energy for the boundaries is such that the minimum energy state of a powder like that has the maximum contact between grains. I hesitate to point this out, but that's another thermodynamic thing.

Jim

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Iron Nickel Cobalt

those are the three elements that have unpaired d electrons, and hence show ferromagnetism. Manganese can also be ferromagnetic, if diluted, for example, certain Mn:bronzes do this.

Jim

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benwoodward.com

WC (what's TC?) is not a cemented carbide. It's a hard, high-strength "engineering" ceramic, just like silicon carbide, aluminum oxide, or titanium nitride. So are TiC, TiAlN, etc., etc.

You can make a sintered carbide/metal composite out of them by mixing powders of the carbide(s) and the metal(s) and then pressing and sintering them into a solid mass. In fact, that's exactly what they do to make "carbide" tools. d8-)

Ed Huntress

Nickel is magnetic. Once the Canadian Nickel was Nickel. I used them in lab to demonstrate the certain temp that the magnetic properties vanish. :-)

another example : Lead Zirconate Titanate (PZT) Curie temp of 350

Curie temp - Ferromagnetic phase transitions - Curie Temp. Fe - 1033C - remember heat a rod of steel until it no longer attracts a magnet... Ni 627 C CrO2 380 C

On and on.

Rust is a slang term for Oxidation. Mostly ferric due to the color. item 4 is a catch all!

" 1. Any of various powdery or scaly reddish-brown or reddish-yellow hydrated ferric oxides formed on iron and iron-containing materials by low-temperature oxidation in the presence of water. 2. Any of various metallic coatings, especially oxides, formed by corrosion. 3. A stain or coating resembling iron rust. 4. Deterioration, as of ability, resulting from inactivity or neglect. 5. Botany. 1. Rust fungus. 2. A plant disease caused by a rust fungus, characterized by reddish or brownish spots on leaves, stems, and other parts. 6. A strong brown. " Martin

Nope

Tungsten carbide is not necessarily WC. The carbon content can vary. Also what is generically referred to as "tungsten carbide" frequently has other carbides present e.g. tantalum carbide is present in some products.

I don't know of any process in use where tungsten carbide is cast. We made a lot of it and it was all "cemented carbide" where cobalt is the usual binder.

Silmanal is a permanent magnet. Composition?

None of the elements usually classified as ferromagnetic are present in that alloy.

Aluminum is attracted to a magnet and certainly is not ferrous. It is classified as paramagnetic but paramagnetic materials are in fact magnetic. Off hand I can't think of any material that isn't ferromagnetic, paramagnetic, or diamagnetic.

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.

Ed Huntress

Well I disagree WC is not a ceramic.

Take a look at a dictionary definition.

We called them cermets and we probably made more of them than any other manufacturer.