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Bizarre Properties of Glass Allow Creation of "Metallic Glass"
VindictivePantz writes to mention that scientists have discovered some bizarre properties of glass and are already applying that knowledge to create what is being called "metallic glass." "The breakthrough involved solving the decades-old problem of just what glass is. It has been known that that despite its solid appearance, glass and gels are actually in a 'jammed' state of matter — somewhere between liquid and solid — that moves very slowly. Like cars in a traffic jam, atoms in a glass are in something like suspended animation, unable to reach their destination because the route is blocked by their neighbors. So even though glass is a hard substance, it never quite becomes a proper solid, according to chemists and materials scientists."
It's not "Metallic Glass", it's Transparent Aluminum ...
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
My first thought is transparent aluminum from Star Trek IV. Only to discover we're closer than I'd think...
This is crap. There have been windows of old buildings "sagging" upwards. The old technology of making windowpanes resulted in glass of uneven thickness, and it makes sense to install it the thick side down. Sometimes the installers did not care enough.
The term glass refers to the structure/lattice. Not to the substance we commonly refer to as glass.
Glass does not "flow". Perhaps you've read such articles, and they are assuredly all bullshit.
Materials scientists call glass an amorphous solid.
It's widely known and widely taught, but it's not so. Glass does not flow at any measurable rate at room temperature. Glass at room temperature is an amorphous solid, not a liquid.
http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass
Except, as noted above, that's not true at all. You learned it in high school because you had a bad science teacher, and shame on "livescience.com" for perpetuating such nonsense. Glass is an amorphous solid, not a 'slow liquid.' It shares one or two characteristics with supercooled liquids, but it is different in several important ways.
First of all, we've known about metallic glasses for years. There's a melt-spinner in the basement of my matsci building that we use to make metallic glasses. Their properties have been fairly well-studied.
Second of all, I don't really like the experiment that these people conducted. They simulated atoms during solidification, but they used microspheres within ANOTHER medium. With glasses, during there is no matrix material within which other molecules are moving. I find their model and extrapolation to be questionable. We are still trying to thermodynamically understand the glass transition and the solid amorphous state compared to the solid crystalline state.
Transparent Aluminum isn't fiction and never was.
Al(2)O(3) is sapphire. Personally I wear a watch made of Titanium and Sapphire.
Aside from repeating the old myth that glass can actually sag over hundreds of years, the article says very little. Perhaps a bad summary.
The jist of linked the story is:
A group of scientists in Bristol, Canberra and Tokyo used a material (doesn't say what) analogous to glass, not glass. This material is easier to study. Using this material they claim they were able to understand better what happens on the atomic level as it solidifies, and why it never really becomes a crystal. Nowhere in the article does it explain why this will lead to "metallic glass"
Here is an abstract for the original article. Pretty complex wording, but nothing about metallic glass.
If the answer is war, you are asking the wrong question
Thank you!! I was going to write something very much like this. Having earned two degrees in science, one a M.S. which largely dealt with material physics, I can say that all materials flow, given enough time. In fact, the term 'rheology' (the study of properties and deformation of materials) comes from the Greek verb rheo, meaning "flow." There's even a Plato quote in there: "All things flow." That being said, the ability of glass to flow is NOT what makes it special. Instead, it is that glass does not posses a crystalline structure, rather, it is an amorphous material. The chemical constituents that make up glass have not combined to form an orderly and repetetive atomic structure of regular, well defined chemical composition. This (at least in part) is what lends glass its special properties. I too had a public school teacher that tried passing on that same misconception, and yes, it is a shameful thing that it continues to get passed along, even by such "reputable" sites as livescience.
From TFA:
An icosahedron has triangular faces. You were thinking of a dodecahedron, perhaps, which has pentagonal faces? The icosahedron's only relation to anything pentagonal (that I'm aware of) is that its dual polyhedron happens to be a dodecahedron.
The only reason it can is because all metal drivers have to conform to a specific standard set by the Golfing industry in order to be qualified for use in tournaments.
He probably made it without regards to this standard, so obviously yes it probably did hit it farther.
Glass is not a liquid of any kind, "technically" or otherwise.
Glass is a solid.
Glass is not a crystalline solid.
Glass is an amorphous solid.
Yes, I am a materials engineer.
Slashdot is my Mercer Box.
try 24 years, and he said at the time that it would take decades to figure out the formula.
I thought this was an urban legend:
"The deceptively liquid-like behavior of glass can be seen when you look at glass in the windows of an old building. The glass begins to sag and distort internally over the centuries, due to the effect of gravity."
This was because old glass making techniques used a spinning wheel to flatten and cool the glass so that one edge was slightly thicker when it was cut into the desired pieces. The whole sagging myth was made up. A common citation for rebuffing the myth is egyption glass that has held its form for much longer than the old english buildings.
) Human Kind Vs Human Creation
) It'd be interesting to see how many humans would survive to serve us.
Unmitigated crap. I hope to god that this was due to the journalist liberally spicing the thing up with his/her own misconceptions. Glass is not a liquid, it does not flow measurably over any reasonable time period, and metallic glass has been around a while. Furthermore, metallic glass does have ceramic properties. Metals are largely useful due to weldability, machinability, ductility, and malleability. Mettalic glass does not generally share these properties. The article is written terribly - "particles called colloids"? Come on, how did this get on slashdot?
Reading down, it seems that I was taken in. It's an urban myth that it's an urban myth that it's an urban myth.
Michael Reed, freelance tech writer.
Glass is Silcon based,
Transparent Aluminum is Aluminum based, it is also known as the gemstone White Sapphire and looks much like diamonds. In fact it has been used for diamond like effects, but doesn't have the brilliance of diamonds (due to different reflective indexes).
Glass MOHS: ~ 5.5
Transparent Aluminun: MOHS = 9. Much harder, better crystaline structure, denser.
And as far as the article's claims, all solids move, but glass definitely is an abnormal material.
they also placed the glass with the thicker area on the bottom because it was heavier, and it's a better idea to put the heavier part of the glass nearer the bottom of the frame. This led to practically all of those panes being installed thicker-side-down. So I suppose you could say gravity was responsible for the pane thickness variance... indirectly.
I work for the Department of Redundancy Department.
Because the invention came from a plexiglass company in San Francisco in the 80's.
For those of you who don't know, that use of the LDS acronym is a refrence to Star Trek IV (the source of all this transparent aluminum talk).
I know these posts are not serous, but the term metallic glass does not refer to transparent metals, but rather metals with an amorphus structure. Metallic glass lacks the fracture points associated with the crystal lattice of metals. This means that metallic glass does not fagigue over time as normal metals would. I believe that metallic glasses were first discovered by rapidally cooling laminants of titanium (I think I read somewhere that a WW2 nazi scientist fisrt discovered them).
Actually, it's even late for a 50th anniversary. http://en.wikipedia.org/wiki/Metallic_GlassSee the wikipedia article.
or this?
If it is metallic then it can't be transparent. You know "sea of electrons" stuff. Electromagnetic fields wont penetrate it due to the skin depth of metallic solids. Unless the conduction is anisotropic, then it would be much more interesting that "transparent aluminium".
Bitter and proud of it.
If you discount the medium gel could be considered a, -for lack of a better term- jammed precipitate. The whole point of TFA was that gel can be used to model the particle-interaction that takes place in glass because both can't settle into a more stable state.