Tungsten Carbide

Sumguy

Golden Member
Jun 2, 2007
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My mom bought me a tungsten carbide bracelet as a graduation present. It only cost $70, which is not a complaint considering how strong the metal seems.

I need it resized. Seems simple enough, but five jewelers owned themselves trying to remove those little metal rods that hold the bracelet together. To put it simply, tungsten>whatever metal those prods were made of. Two others admitted they had no idea wtf to do with it.

After all the wailing, there isn't even a single minute scratch on the thing. I even took a knife sharpener to the thing and little bits of iron were flying off. So...anyone have any idea how I'm supposed to go about this?
 

orakle

Golden Member
Nov 28, 2002
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You know tungsten carbide is one of the hardest materials in existence right? Maybe if you found a jeweler with some high-carbon steel or tungsten carbide tools he could do something. Good luck.
 

gorcorps

aka Brandon
Jul 18, 2004
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Yeah it's pretty hard shit. It's awesome because once it's polished it'll take a hell of a lot to scratch it up again.
 

SagaLore

Elite Member
Dec 18, 2001
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It would probably be cheaper to buy an identical bracelet of the right size. Then sell the one you got.
 

SagaLore

Elite Member
Dec 18, 2001
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Just saw this on wikipedia:

Tungsten carbide is four times harder than titanium, twice as hard as steel

Wait, what? Steel is harder than titanium? :confused:
 

gorcorps

aka Brandon
Jul 18, 2004
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Originally posted by: SagaLore
Just saw this on wikipedia:

Tungsten carbide is four times harder than titanium, twice as hard as steel

Wait, what? Steel is harder than titanium? :confused:

Well most steels aren't, but there are higher carbon steels that are harder than titanium. I don't think they're used in anything common these days except maybe anvils and blacksmithing tools.
 

jdoggg12

Platinum Member
Aug 20, 2005
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There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger
 

destrekor

Lifer
Nov 18, 2005
28,799
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Originally posted by: SagaLore
Just saw this on wikipedia:

Tungsten carbide is four times harder than titanium, twice as hard as steel

Wait, what? Steel is harder than titanium? :confused:

Yes, but steel is much heavier, and prone to corrosion. Titanium can be said to be stronger in a strength-to-weight ratio, iirc, as titanium is a lighter metal, and far less prone to corrosion.

+
 

Sumguy

Golden Member
Jun 2, 2007
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Originally posted by: jdoggg12
There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger

Actually, I read somewhere that the ring shatters like glass when you compress it with a hand vice. Apparently its a ceramic metal (?) and can't bend worth shit.
 

gorcorps

aka Brandon
Jul 18, 2004
30,739
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Originally posted by: Sumguy
Originally posted by: jdoggg12
There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger

Actually, I read somewhere that the ring shatters like glass when you compress it with a hand vice. Apparently its a ceramic metal (?) and can't bend worth shit.

Not entirely true. On it's own it's not a ceramic metal, but when it's bonded with cobalt it is... which is what they do when they need to use it for drill bits or cutting tools.

However hardness is generally inversely proportional to ductility, so anything incredibly hard will more than likely just shatter vs. bend. But it'd take a whole lot of pressure to do so and I'm not sure I'd like that on my finger.
 

Fenixgoon

Lifer
Jun 30, 2003
32,621
11,737
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Originally posted by: gorcorps
Originally posted by: SagaLore
Just saw this on wikipedia:

Tungsten carbide is four times harder than titanium, twice as hard as steel

Wait, what? Steel is harder than titanium? :confused:

Well most steels aren't, but there are higher carbon steels that are harder than titanium. I don't think they're used in anything common these days except maybe anvils and blacksmithing tools.

you don't need a high carbon steel, actually, to get a very hard steel. you simply need to heat it between 800-1000C and quench in water. that will give you an incredibly hard, but *very* brittle steel known as martensite :)


as far as the tungsten carbide ring goes, most places simply exchange the ring i think- tungsten carbide is incredibly strong and incredibly hard, and therefore difficult/impossible to resize
 

Howard

Lifer
Oct 14, 1999
47,982
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Originally posted by: gorcorps
Originally posted by: Sumguy
Originally posted by: jdoggg12
There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger

Actually, I read somewhere that the ring shatters like glass when you compress it with a hand vice. Apparently its a ceramic metal (?) and can't bend worth shit.

Not entirely true. On it's own it's not a ceramic metal, but when it's bonded with cobalt it is... which is what they do when they need to use it for drill bits or cutting tools.

However hardness is generally inversely proportional to ductility, so anything incredibly hard will more than likely just shatter vs. bend. But it'd take a whole lot of pressure to do so and I'm not sure I'd like that on my finger.
"cermet"
 

SlowSpyder

Lifer
Jan 12, 2005
17,305
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I have a tungsten ring, from what I've read you really can't resize tungsten... it's too hard and strong as your jewler found out, OP. :) You should be able to exchange it for your size, that's generally how tungsten jewelry is handled.
 

fstime

Diamond Member
Jan 18, 2004
4,382
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Originally posted by: jdoggg12
There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger

A common misconception held concerning Tungsten Carbide rings is they cannot be removed in the course of emergency medical treatment, requiring the finger bearing the ring to be cut off. Emergency rooms are usually equipped with jewelers' saws that can easily cut through gold and silver rings without injuring the patient when the ring cannot be slipped off easily. However, these saws are incapable of cutting through tungsten carbide.

Tungsten carbide rings can actually be removed in an emergency situation by cracking them into pieces with standard vice grip?style locking pliers. Although standard ring cutting tools cannot be used due to the hardness of this material, there are specialty cutters available that are just as effective on tungsten carbide as they are on gold and platinum.
 

jdoggg12

Platinum Member
Aug 20, 2005
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I'm only going off of what... gasp... i was told by a Dr. at the stanford hospital
 

Sumguy

Golden Member
Jun 2, 2007
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Originally posted by: SlowSpyder
I have a tungsten ring, from what I've read you really can't resize tungsten... it's too hard and strong as your jewler found out, OP. :) You should be able to exchange it for your size, that's generally how tungsten jewelry is handled.

Meh, guess I got owned :p I'll still try to get it resized, I figure that if they get the pins in, there should be a way to take them back out. If that doesn't work out guess I'll send it back in to be resized by the company or exchanged for a smaller one.
 

zoiks

Lifer
Jan 13, 2000
11,787
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My fishing boots have tungsten carbide studs that grip the kelpy, algae covered rocks that I fish from. The boots are almost to the breaking point but very little sign of wear on the studs.
 

Connoisseur

Platinum Member
Sep 14, 2002
2,470
1
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Originally posted by: BouZouki
Originally posted by: jdoggg12
There's a reason that the medical world tells you not to have tungston carbide rings - if ever you hurt your hand and it swells up, you have a VERY good chance of losing the finger(s) with those rings on them b/c there's nothing that will be able to cut if off your finger

A common misconception held concerning Tungsten Carbide rings is they cannot be removed in the course of emergency medical treatment, requiring the finger bearing the ring to be cut off. Emergency rooms are usually equipped with jewelers' saws that can easily cut through gold and silver rings without injuring the patient when the ring cannot be slipped off easily. However, these saws are incapable of cutting through tungsten carbide.

Tungsten carbide rings can actually be removed in an emergency situation by cracking them into pieces with standard vice grip?style locking pliers. Although standard ring cutting tools cannot be used due to the hardness of this material, there are specialty cutters available that are just as effective on tungsten carbide as they are on gold and platinum.

Heh you really should be giving credit to wikipedia. Paraphrasing is one thing, but that's a direct copy... I know cause I was about to do the same thing.