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New Alloy Stronger Than Fe And Ti
SoCalChris writes "According to this article on MSNBC.com, researchers at CalTech have discovered a new alloy that is stronger than steel and titanium, can be cast in a mold like plastic, and sharpened like glass. The first plans for the new alloy are to be used in golf clubs, baseball bats, skis, and cell phone covers."
Fe is iron, not steel. Steel is an alloy, not an element.
As they say in the article it isn't anything new. They just make it a bit thicker, why is this even news?
But seriously, this looks very interesting, I imagine car and aircraft manufacturers could use a metal such as this. A lot depend on the cost to make and machine it though.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
The article mentions 'twice as strong as steel and titanium', yet does not quote which 'strength' this refers to (or gives any real objective data). I suspect it might have high tensile strength (hard to break by pulling it apart)...
But materials like this tend also to be brittle, and do not do well in other kinds of loading. Take 'fatigue' loading, for instance. This measures how well it holds up to repeated loads, such as crankshaft in a car. Materials with uncrystalline structures not only tend to fail quickly under repeated loads, but also tend to fell catastrophically (breaking in two, instead of gradually bending).
The article doesn't give enough info to verify this - just my thoughts. In material science, you generally have to make a compromise - in this case, tensile strength against fatigue life.
Quotation from article:
"Liquidmetal Technologies chief executive John Kang stands with a sample of an armor-piercing shell made of Liquidmetal -- which could one day replace depleted uranium in tank shells."
I think weapons design is still in.
Sure, just like salt (sodium and chlorine) will kill you if you breathe it, and water (hydrogen and oxygen) is highly flammable.
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
The big deal in auto safety isn't in getting the vehicle to withstand a violent impact. It's in making it more likely that the passengers will survive such an impact. Ever hear of 'crumple zones'? The idea there is to sacrifice the vehicle, getting it to absorb much of the energy of the impact, in order to improve the passenger's chances of survival.
Would you want to buy a car that would come away from a head-on collision with only minor damage to the vehicle itself, but that would leave the driver splattered all over the interior?
- You don't want a car to withstand a front end collision. Even if cars could be made indestructible, they wouldn't be. Havn't you ever heard of a crumple zone? You want the car to decelerate as slowly as possible, which mean crushing as much as possible.
Bull Fucking ShitYou know those commercials where the car hits the brick wall and they show how well the car 'crumples' up as a safety feature?
I hate those.
If I hit a brick wall, I WANT TO KEEP ON GOING RIGHT ON THROUGH fuck the brick wall and fuck crumpling up like a wuss, the *brick wall* can
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Now people will be able to sharpen their cellphones and use them as weapons directly, rather than having to use them as only part of the main weapon that is their SUV...
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Cars don't withstand head-on collisions for a reason. They crumple to soften the blow for passengers. Here's why:
.0254 m
.0254 m) = -14162 m/s^2
Let's take a 60 mph head-on collision with something massive enough that it doesn't move when the car hits it. Assuming that the car doesn't deform at all, the passengers will have to go from 60 mph to 0 in the distance of about an inch (liberal estimate for seat belt play and expansion).
'scuse me while I whip this [physics book] out:
v^2 = v0^2 + 2*a (x - x0)
Solve for a:
(v0^2-v^2)/(2*(x-x0))
v0 = 60 mph -> 26.8224 m/s
v = 0 mph -> 0 m/s
x = 0 in -> 0 m
x0 = i in ->
(26.8224 m/s ^ 2 - 0) / (2*(0 m -
(14162 m/s^2) / (9.8 m/s^2) = 1445 G's.
If you were unlucky enough to be in this car, you wouldn't just die. You would splash. I friend of mine just informed me that the tensile strength of a seatbelt is 15 tons, and a 150 lb person would exert 108 tons on the seatbelt and splash into the dashboard or steering wheel.
Moral of the story: if they ever do make a car that stiff, don't ever get in it.
This isn't going to replace structural metals any time soon. How do I know? I did dynamic planar compressive strain experiments and ABAQUS on this stuff and composites with this as the matrix for my senior thesis.
Being a metallic glass, it has all sorts of crazy properites, as mentioned in the articles, but when it reaches the yeild strength it shatters (at least in non-composite form).
Also, because it is a metallic glass, it is inherently a meta-stable solid.... metals usually have relatively simple crystal structures, and thusly crystalize quickly with relatively small undercooling. The clever trick with this stuff is that it's a mix of four or five metallic elements that have a large span of atomic radii (this stuff is Zr-Ni-Cu-Ti-Be, various weightings of each, usually the Ni=Cu=Ti). Anyhow, when it finally does crystallize, whether due to heat, fatigue or constant strain, it forms a pretty complex crystal structure (I don't recall which one offhand) that allows very little motion of dislocations. Thus, it's super brittle when in it's thermodynamically stable state. Moreover, even with this clever alloying, it still requires high cooling rates to avoid crystallization from the melt, and is thusly hard to cast into large ingots.
Thus, whether it takes too hard an impact (can never be a tooling metal or knife, in pure form) or is under strain for too long (can never ever be a structural metal - too flaw sensitive in pure form and too expensive to process and machine in composite form) it will fail catastrophically.
Basically, this means it's pretty useless for most applications metals are required for (due to lack of crystal structure it's also a poor heat conductor - sorry overclockers). And because it is opaque, it can't be used for traditional glass applications. Liquid Metal has been around for a while trying to push the golf clubs, for at least three years, more like four or five, so I'm not sure what the sudden attention is for. We ran a back of the evelope calculation in my research group: Say you're on the links, and you mis-strike the ball, and hit a large rock in the ground with a non-composite liquidmetal club... basically you'll shatter the face of the head (only the face is amorphous due to process/cost/strength issues), sending shrapnel flying into your ankle. Yum.
Still, from a physics perspective, this stuff is really interesting due to its completely artificial nature (you'll never find anything close to this in nature) and odd mechanical properties (it's the metallic version of flubber). Commericially, in bulk form, I'd say they should shy away from structural applications and perhaps try transformers, where the thin film versions of amorphous metals have significant gains over silicon.
There are so many questions being asked here about details... The company website has much more information than this article. Go to the source.
" a new alloy that is stronger than steel and titanium"
By mass or by volume? Stronger with reguards to tension, compression, or shear? Or some combination?
Heck, I can think of a building material that is more easily molded than either of those two metals and is actually stronger in many ways. It's called concrete. Just don't try to put it under tension or shear...