Apple Buys Out LiquidMetal Patents To Stay One Step Ahead In Materials Game

LiquidMetal is substantially stronger than other metals. It's not about the bouncing. It is perfect for saving weight and especially thickness. At the time the only issue was cost, but I assume they have covered good ground on that front over the last decade.

As for the technology itself, my understanding is that they cool the alloy in a particular way that leaves its molecules unaligned -- like a liquid. This makes it much stronger.

http://en.wikipedia.org/wiki/Liquidmetal

Liquidmetal alloys achieved yield strength of over 1723 MPa, nearly twice the strength of conventional crystalline titanium alloys.

That's some material science porn, liquid metal products can use a fraction the amount of material to achieve the same strength as other metals. This will be great for bikes, electric cars, knives, all types of springs, spaceships, hammers, more efficient engines, those desktop swinging balls... Breakthroughs like this don't happen often.

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.

This means that, when everyone else has caught up to their machining / laser manufacturing, they'll suddenly have this magic ability to create strong materials is very unique shapes with very high economies of scale.

At least that's my take...