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How To Tell If It's Really Titanium
With the growing popularity of titanium, some disreputable merchandisers are passing off other materials as the more expensive metal. Popular Science looks at a surefire way to prove what that credit card/crowbar/ring is really made of. "Hold any genuine titanium metal object to a grinding wheel (even a little grindstone on a Dremel tool will do), and it gives off a shower of brilliant white sparks unlike any softer common metal. The sparks are tiny pieces of cut titanium--the friction of the grinder heats them till they burn white-hot. Hold a grindstone to the shackle of a "titanium" padlock from Master Lock, however, and you'll instead see the telltale fine, long, yellow sparks of high-carbon steel."
The method in TFA sounds like it would really scratch up whatever you're trying to test. Is there a way to run a test without damaging the object?
"It is a denial of justice not to stretch out a helping hand to the fallen; that is the common right of humanity."
Think the store will mind if I bring a dremel with grinding wheel to the store with me? For testing purposes of course...
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Wtf is with these fake links? Do you get money or something for that stupid city?
Apparently my wife's jewelry was all genuine titanium!
If the object in question is constructed from a single material, then a density test should work. Use water displacement and a scale to determine the volume and mass, respectively. From that you can calculate the density and compare the value to the actual density of titanium. Of course, this won't work if the object merely has titanium components and it cannot be disassembled. . .
It heats white hot almost instantly, and when you thumb the oxygen cutting lever, you get the most amazing shower of white sparks - like fireworks - very pretty!
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
The author of this Popular Science article, Theo Gray, also recently relaunched http://www.periodictable.com/ Thousands of elemental pictures and videos are available there, all linked in with his Popular Science series.
This is very much a point where Hanlon's Razor can be applied.
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Parent is warning about fake link in the GP. How exactly is this offtopic?
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Man, I just tried this with a new package of Energizer Tianium, and the spray burned a hole through my skin!
You can be sure I'll be returning these "titanium" batteries just as soon as I'm back from Emergency!
a: Titanium is not ferromagnetic, and hence it is not attracted by magnets as strongly as iron is ( the difference in force should be orders of magnitude ).
b: Titanium's density is 4.5g/cm^3 , iron is 7.8g/cm^3
c: Titanium is corrosion resistant to dillute sulfuric and hydrochloric acid, iron is not.
Next up: Test if your explosives have gone bad by detonating them.
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The article I clicked on - the only link in the summary as I write this - leads to a page that has both a huge photo on top showing the two side by side (titanium vs steel) but also a video where they grind various items. The difference is very noticeable.
=Smidge=
Apparently, Google has "interesting" sense of humor regarding titanium products.
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I read a story about a couple who loved bicycling (and loved their titanium bicycle frames). They decided to have rings made from titanium.
One day the guy had some kind of accident, and his ring finger was mashed; it swelled up badly. They took him to the emergency room. In the ER, someone got out the cutters to cut the ring off the swollen finger. Whoops, titanium. The cutters (probably simple diagonal cutters) had no problem with the usual soft gold rings, but titanium was too hard! They wound up getting a Dremel tool or the equivalent and cutting the titanium ring off (very carefully, I imagine).
The moral of the story: if you get a titanium ring made, maybe you should wear it like a necklace.
P.S. Merry Christmas everyone.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
I know an ER doc who thought the same thing, until somebody came into her ER with one, and it was as trivial to cut off as anything else. Even if they lack a proper cutting tool, you can just squeeze it until it shatters. Titanium is strong, but it's not like a ring made of the stuff is somehow immune to being cut or broken. Hospitals are full of interesting tools, and it sounds like even in your story, they improvised fairly well.
Useful trivia:
Steel is a blend of iron and carbon. Mostly iron, in all its incarnations, and iron is always magnetic.
High-carbon steel is very hard but a bit brittle, while steels with less carbon will usually deform before they crack. There is always a compromise between hardness and toughness.
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It has good tensile strength and low weight but few applications warrant the additional expense.
Wrong. Several I can think of. Here's a couple that I have personal experience with.
Bicycles. A Ti bike is a noticeably different ride than other materials.
Eyeglasses. Steel contains quite a bit of nickel. Many people are allergic to it, and get a rash when in constant contact with it. So, in eyeglasses, you have a choice between regular steel, Ti, or plastic. Guess which wins.
...iron is always magnetic.
That is a big fallacy. There are some alloys in which iron is around 98-99% which are non-magnetic (think unusual alloying elements like niobium and rhenium).
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Gloves + rotating grinder = BAD. You don't want a glove to get caught in that, your hand goes with it. Better to be burned by some sparks than to lose a few fingers (at best).
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MERRY CHRISTMAS!
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If you were testing Adamantium, those sparks were probably from your grinding wheel being worn down to a nub.
The higher the technology, the sharper that two-edged sword.
Steel is actually an alloy containing predominately iron, usually has a good amount of precipitated Ferric Carbide crystals , ferric-Carbide in solution with the iron and often trace elements and occasionally minute amounts of pure carbon which is detrimental. The amount of carbide in solution and precipitated greatly controls the physical properties of the metal and is controlled by the heat treatments the steel is exposed to during manufacture.
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.. not hydraulic
Iron isn't always magnetic, when heated to or above it's normalization temperature it loses it's magnetic properties, you can hold a piece of steel suspended with an electrimagnet in a kiln and heat it, when it reaches it's normalization temp it will fall to the kiln floor.
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You don't even need that much heat. Just warm it in your hands, and if you get a faint pine smell it's amber.
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I tried the method with my tennis racket. Indeed, it *was* titanium.
All the titanium hype is just pure marketing BS anyway.
They're capitalizing on the idea that titanium is high-tech and expensive. Which it is. But that's relative steel
and aluminum. Aluminum costs about $2,500 a (metric) ton. Titanium, on the order of $50,000/ton. Contrast that to gold, which'll cost you around $25,000,000/ton.
So titanium jewellery? I'll pass. In fact, I read an article where a metals wholesaler said that he didn't even bother to charge for the small amounts used for designer jewellery.
It's all just a marketing stunt. Titanium isn't actually better than the metal it's replacing a lot of the time. To take an example, I saw an expensive titanium camp stove (as opposed to aluminium). The stupidity of that, besides being heavier, is that titanium sucks as a heat conductor, in particular in comparison to aluminum (what's your CPU heatsink made of?)
Instead of asking themselves "Is it really titanium?", people need to ask "Why does it need to be titanium?"
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Depends on the type of stainless. Austentitic is not ferromagnetic, while martensitic is.
Most steels are magnetic to various degrees. However, when designing some stuff that would be used in an MRI suite, I did some research and found that some grades of stainless steel - specifically, 300-series stainless steels (302, 304, 316, etc.) - are more or less nonmagnetic. They can't be used inside the bore of the scanner, but that's mostly because it screws up the uniformity or the magnetic and RF fields necessary for imaging. This was a handy discovery for me, because sometimes aluminum and plastics aren't strong enough, and titanium is a lot harder to work with.
After having steel framed glasses for many years, and started getting a skin reaction exactly where the frames touch my skin...I asked the optometrist about it. She said "oh...you have nickel allergy. You need something else besides steel frames."
Bought the (too expensive) Ti frames, and the condition went away almost immediately. Within days. Couple years later, tried another pair of steel ones. It started coming back. All Ti from then on.
And the Ti frames are significantly stronger/more flexible.
Titanium is a woman's metal. Real men use Tungsten.
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We were building a rig for a show and there were a lot of surplus aitcraft parts around. I found a large bracket that was perfect but it needed an extra hole drilled in it. The piece was light enough I assumed it was aluminum. I was using a hardened drill bit that should have cut through stainless. After five minutes I checked it and I barely scratched the surface. Aircraft Aluminum can be fairly hard but it seemed rediculous so I tried again but still nothing. I flipped over the part and there stamped/cast on the otherside was Titanium. Needless to say I gave up. All I managed to do was kill a good drill bit. If it seems really light for it's size and can't easily be scratched there's a good chance it's Titanium.
And in fact, some soldering iron thermostats use this property. When the iron is cold, a magnet pulls the contact closed. Once it heats above the Curie point, the magnet lets go and the contact breaks.
someone please tell me how to tell if there's real platinum in my Capital One® platinum Card, I always want to know.
If the object is solid, why not use the archimedes principle?
It worked for gold, why not for titanium?
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Aluminum most certianly *DOES* burn. Though fairly difficult to ignite, aluminum burns ferociously and spectacularly and is notoriously difficult to extinguish, as the crew of the HMS Sheffield learned much to their dismay. The fuel of the Space Shuttle's solid rocket boosters is aluminum. And aluminum is the fuel component of thermite.
I think that the "scientific" opinion of anyone so clueless as to try to claim that aluminum won't burn should be discarded with the lowest grain of salt
cya
john
Imagine all the people...
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Hmmmm...I wonder if this works with magnesium?
Actually, titanium holds an edge very well. I've used my diver's knife with a titanium blade for 7 years and have not had to sharpen it once. It's still just as sharp as the day I bought it. I dive several times a year and use it to dig for shark's teeth, as a tool, and for protection. Not a scratch, a mar to the edge, nor any rust to the blade.
Impetuous! Homeric!
Unless a hot chick injects you in the ass with a syringe full of iron so a rather magnetic villain can escape from a plastic cell.
How bout a blow torch, chlorine gas or liquid oxygen? :)
:)
Even bulk titanium metal is susceptible to fire, when it is heated to its melting point. A number of titanium fires occur during breaking down devices containing titanium parts with cutting torches.
When used in the production or handling of chlorine, care must be taken to use titanium only in locations where it will not be exposed to dry chlorine gas which can result in a titanium/chlorine fire. Care must be taken even when titanium is used in wet chlorine due to possible unexpected drying brought about by extreme weather conditions.
Titanium can catch fire when a fresh, non-oxidized surface gets in contact with liquid oxygen. Such surfaces can appear when the oxidized surface is struck with a hard object, or when a mechanical strain causes the emergence of a crack. This poses the possible limitation for its use in liquid oxygen systems, such as those found in the aerospace industry.
http://en.wikipedia.org/wiki/Titanium
Call me paranoid, but I think I'll stick to gold if I ever wear jewelry. But interesting to know if you're ever in a McGuyver type situation.
If it weren't for slashdot, I would never know amazingly pointless facts like this one. Thanks, slashdot.
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Sorry, that's not my understanding of the metal's properties. I guess for digging around in the sand, you don't really need a fine edge, but nothing to my knowledge compares to the ability of steel (esp. high-carbon steel) to hold an edge. High-carbon steel is very brittle, which helps it to hold an extremely sharp edge; this is why Japanese samurai swords were forged to have one side harder than the other side, so the sharp side would be extremely hard, but the other side would be less hard and more strong (done by using clay on one side during quenching) so that the blade as a whole wouldn't break easily.
There's a reason no other knives are made of titanium, or anything besides steel for that matter.
Titanium is known to be a very strong metal. If you know anything about metallurgy and its terminology, strong and hard are different properties, and usually work against each other: a metal is usually strong, but not hard, or vice versa, not both. Steel can be made to be hard, but brittle, or strong (which is more flexible) but not very hard.
Anyone with a titanium ring knows that it's not a hard metal at all: it's easily scratched unless it has a protective coating (usually diamond). Sure, it might prevent a automatic pressure door on an undersea rig from locking you in, but it doesn't hold a sharp edge at all.
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