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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.
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.
Because the difference between "less than a millimetre thick" and "arbitrarily thick, and castable without needing to be machined afterwards" is huge. Also, the science behind the "making it a bit thicker" is nontrivial. The process behind the old-style, which produces films, is totally different than the process behind this new one. It's not like making a golf club is anything like making a really thick film. This is old news in that the research was done in 1992, but it's new news because it's finally beginning to be pushed in the industry, where we'll actually see any benefits from it.
This is a self-referential sig
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
- 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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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.