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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."
How bizarre.
Beam me up, Scotty!
Is this the aluminium glass that Scotty spoke of?
Meh
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
So am I according to an ex-girlfriend. Thanks, I'll be here all week. Try the veal. Tip your waitstaff.
Well, there's spam egg sausage and spam, that's not got much spam in it.
My first thought is transparent aluminum from Star Trek IV. Only to discover we're closer than I'd think...
See? That guy in SF did invent it, just like Scotty said.
Mission: To provide products that consume time and energy as entertainingly as permitted by the laws of thermodynamics.
How bizarre.
I like to place meaningful quotes in my sig, so people will know that I know what meaningful quotes are.
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.
Either way, be prepared to see them as band names any minute now. Or perhaps the band name is "Metallic Glass", thier first album is "Transparent Aluminum"
There seems a transparent aluminum story every couple of years
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Glass does not "flow". Perhaps you've read such articles, and they are assuredly all bullshit.
Materials scientists call glass an amorphous solid.
no, actually we've known that to be an untrue myth for a while, what's happened here is that we've suddenly forgotten it!
One of the interesting aspects of this article is how it highlights the usual thermodynamic balance between entropy and free energy. States of matter in the equilibrium phase attempt to simultaneously maximize entropy, a measure of the statistical likelihood of a given state, and minimize the amount of energy "stored" in the given arrangement of molecules.
The most favorable condition is often a compromise between maximum entropy and minimum energy as highly ordered states, such as tetrahedral or other crystalline arrangements, often act to reduce the amount of stored energy due to minimized interatomic and/or intermolecular interactions and related factors. Pure crystals of substances will often form because the energetic "advantage" of the highly ordered crystalline state is often great enough to overcome entropic barriers.
The model that the researchers propose is interesting because the crystalline state itself introduces a degree of energetic disadvantage due to what is described as "cramming" of the individual crystalline unit cells. I wonder what models they used to form their hypothesis that the glass would eventually form a perfectly crystalline state.
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://starwars.wikia.com/wiki/Transparisteel
This reporter does not know what they are talking about. The comet failed due to stress risers at the corners of the windows, not because of grain boundaries. Let the materials scientists do the writing. Don't let journalists do science writing. Morons.
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.
In my very best Canadian/pseudo-Scottish accent, "Hello computer..."
http://www.google.com/patents?id=Kq4yAAAAEBAJ&dq=4256039 Filing date: Jan 2, 1979
Its also been used in large transformers for years. The "technology advance" here worth noting is in being able to produce it while casting/moulding objects that are not thin and flat. It had been done as sheets for years, but casting a part that is something like 7 times the strength of titanium is much more useful. Unfortunately, the problem to solve is its brittleness. Things that shatter are much less useful.
I am a materials engineer at the University of British Columbia in Canada. I recently did a technical presentation on 'Bulk Metallic Alloys' which seems to be the category of materials this 'glass' falls into. BMG's are very exiting materials, their main advantage over traditional alloys is their ability to store energy in elastic deformation. Esentially, they are the worlds best spring material. However; Be careful with your application in using these materials, they may have properties of strong alloys, but they have failure characteristics simmilar to ceramics. Usually they can fail with little to no warning, and catastrophically at that. Crack formation cannot be tolerated. I would not be comfortable with using this material for plane wings. Possibly the landing gear. This material has its niche in underplating for bodyarmor. Send the bullets back. For more information, a good website is http://www.liquidmetal.com/
Silicon is a metalloid, which has some properties of a metal (or some degree of those properties), and some properties that nonmetals have instead. That's why it can be made into a semiconductor.
That isn't news. This is the big story of 20th Century technology. Exploiting the glass properties of this metalloid is the real news.
--
make install -not war
wow, just confusing... glass slow liquid... just confusing...
Thanks, No-Child-Left-Behind!! LOLz
"Don't let fools fool you. They are the clever ones."
Additionally, I am wondering why the summary compares glass to gel. Gel is a colloidal solution.
...
...
Still waiting for you to put us out of our misery.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
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
... residents of glass houses may now throw stones.
Have gnu, will travel.
/p.s. this will get modded -1 Troll Unlikely since most moderators DO NOT browse at -1. Disappointing, very disappointing.Through-glass antennas are on millions of cars. Don't they exploit this kind of property?
The more important thing here is that they found, through their simulation, that glass is in the jammed state. The relationship between jammed granular materials and glasses is, at this time, uncertain, and is very closely related to research that I am currently performing in the local Physics Dept.
Back in college I knew a prof who made a golf club driver out of metallic glass and it could hit a ball further than a titanium driver or whatever they use now.
"Royall is part of a group of scientists who think that if you wait long enough, perhaps billions of years, all glass will eventually crystallize into a true solid."
tell me a decent geologist cant locate some billion year old glass from a meteor impact, a volcanic eruption or something.
if you can find a sample you should be able to test this.
I was reading the article...
...and now I'm thinkin' Arby's
For example, the world's first jetliner, the British built De Havilland Comet, fell out of the sky due to metal failure. When metals are be made to cool with...
I thought we already had transparent aluminum? Hell, even Scotty used it to save the future way back when!
---- Liquid was a patriot ----
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.
Warning that article contains anti-science! Room temperature glass has a viscosity of 10^22 poise. The viscosity of a liquid controls how fast it flows under gravity. (SAE 30 motor oil has a viscosity of about 1 poise, water is 0.01 poise.) The viscosity of glass is so high that you could wait the entire age of the universe and see no measurable thickening of the glass under earth gravity. Don't believe the "Old Window" myth! Just because glass is a liquid doesn't mean all of our windows will melt out in only a few hundred/thousand/million/billion years
From the page you linked to on wikipedia I found this quote:
"In the technical sense, glass is an inorganic product of fusion which has been cooled to a rigid condition without crystallising."
That is why glass is recognised among physicists as being a liquid, because it has not crystallized. Maybe you should have read the whole page before you linked to it. This is actually a contentions subject but since not enough people here have a phd in crystallography or thermodynamics we are not going to resolve it.
I dont read
Conventional silica glass will flow with enough time and temperature; however the temperature you'd need before anything is noticable in a few hundred years is still a few hundred degrees. Lead is a different story due to the lower melting point and lead church organ pipes have been observed to change shape over hundreds of years. The mechanism is refered to as "creep", and happens under the right conditions whether you have a crystalline structure or a disordered structure like a glass.
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.
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.
This space up for sale.
"...glass is not in an equilibrium state, (although it appears that way to us during our limited lifetimes)..."
Glass is a *very slow* liquid. According to TFA you can note some flow in very old panes which can appear distorted. This is very cool.
Those are my principles, and if you don't like them... well, I have others.
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?
For a General Products #2 hull please.
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.
You may be very competent at being an Anonymous Coward, but you are not a materials engineer. You making the assertion that a meterials engineer would not know if glass is solid (or liquid for that matter) is like a comic book artist making claims about cosmology.
"Prince Glass, Ceramics's son though crystal-clear Is no wise crystal"- John Updike, Dance of the Solids
Read Chapter 9, Fundamentals of Ceramics, Michel Barsoum for a discussion of same. And shout out to all my Material's Science homies who got here first! Mat Sci fo life, boyee!
What would Richard Feynman do, if he were here right now? He'd do some math and he'd follow through!
On the chance that they are right, im gonna go ahead and pre-order some glass armor for the elder scrolls V.
A minor pernickety correction: that's Herakleitos, not Plato. Plato just quoted it.
Oh, wait, yes you are. This post may safely be disregarded. We now return you to our regularly scheduled discussion of cosmology by Stan Lee.
It's not Transparent Aluminum, it's "Unobtanium!" That mystical substance the mechanical engineer's are always using for their designs and then they get so darn frustrated when we give them the bad news.
Bonus points if you know the story about the big three auto company and the PHB who decided he didn't need heat treat. Any heat treaters out there?
What would Richard Feynman do, if he were here right now? He'd do some math and he'd follow through!
Your Jedi mind tricks won't work on us, Physics weenie! Embrace the dark side. And yes, the Physics guys do hate us because applied physics isn't as sexy as blasting muons apart in super-colliders.
What would Richard Feynman do, if he were here right now? He'd do some math and he'd follow through!
"Metallic Glass" implies glass with metallic properties, not a metal with glass-like properties. Perhaps it is technically correct (and perhaps not... I do not know), but the popular perception would certainly be that this is glass (some variant of silica), not metal.
At first, I actually thought TFA was going to be about a way to force silica glass to form a crystalline structure. Not transparent aluminum, but glass with properties similar to aluminum.
But alas, it was not to be.
How about calling it, say, "amorphous metal" instead? I think that's much more descriptive and perhaps more accurate.
Phil, meet Yngwie....
Actually, it's even late for a 50th anniversary. http://en.wikipedia.org/wiki/Metallic_GlassSee the wikipedia article.
Now, in our little joke playing off the Star Trek Movie (IV IIRC), Glass isn't the "Aluminumy" part, it is the "Transparenty" part. Aluminum is "metal based", IIRC. Glass is transparent from time to time.
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
Burn ;-)
You just got troll'd!
May contain traces of nut.
Made from the freshest electrons.
Say goodbye to your Windows logo Slashdot.
Here be signatures
It isn't. I've got a window which is thicker at the top -obviously installed by the apprentice.
No sig today...
First, not all glass is Silicon based, there are a wide range of other glasses out there, they just aren't used in windows.
Second, calling sapphire transparent aluminum is extremely misleading. Sapphire is aluminum oxide (Al2O3), and all the colors of sapphire (ruby, for example) are aluminum oxide with a few impurities like Chromium or titanium. It is transparent because it is a single crystal and the ionic bonds between the Al and O ions cause the electrons to be very tightly bound and not absorb light in optical frequencies.
Finally, the hardness of sapphire is more due to the bond strength of the Al-O bonds. Crystal structure has very little to do with hardness in most cases. However, hardness is a pretty nebulous property, and depending on the measurement technique (Mohs is by far the worst) crystal structure may play a very small role.
Sure it does. Just apply heat and see what happens.
...That this was about some sort of skin for Trillian.....
There's no heavy engineering here but one of the things I've always wondered about was the reason cast iron is still used for high quality reloading presses. Steel would be stronger and lighter. And when cast iron breaks, it just snaps. Then someone who thinks deeper than me pointed out that for this application (which requires parts be held in perfect alignment), catastrophic failure is preferable. If a press were to bend, even a little, it would appear to be working fine but produce poor-quality output. A press needs to either be perfectly aligned or obviously broken.
Good presses are heavy. Among the presses I own, a legendary early Hollywood is my favorite (Trust me, the two serious reloaders in the audience are now highly impressed) and weighs over 40 pounds. I wonder if it would be possible to make one of these from a light, strong material that would never bend, only break, under excessive load?
That would be not just cool but very useful for portable applications.
Would that be with or without a Slaver Stasis field?
An essential optional at only 5M*.
"Kill 'em all and let Root sort 'em out"
Sorry celtic hackr, but you're a little off. There is no such thing as transparent Aluminum. That I'm afraid we'll have to leave consigned to Star Trek. There is however transparent Alumina, Al2O3, i.e. sapphire. Alumina is a crystalline ceramic, and amongst being other places is one of the components of your toilet bowl. It is not transparent there because it is polycrystalline. Window glass is silica based (SiOx) but may contain a variety of other elements as well. When glass is pure SiOx it tends to be called fused silica or something similar, and has a much higher flow point than household 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.
Funny how Wikipedia is outclassing the accuracy of public school teachers. No wonder academics lambast it so much!
So...Wikipedia can be more accurate than "reputable" sites like livescience and also more accurate than public school teachers. Yet school systems and academics continue to dismiss and condemn Wikipedia as inaccurate tripe comparable to graffiti. Maybe it's more a matter of feeling threatened by its utility than genuine criticism?
If glass *actually* sagged visibly on 100-year timeframes in windows, how long would it take for a large telescope mirror to deform to useless?
The 200 inch mirror of the Hale telescope at Palomar is currently 60 years old. That's over 16 feet wide, and some 14 tons of glass.
Telescope mirrors are usually within a few *millionth* of an inch of "perfect" - even an amateur can easily get within 1/4 wavelengh of perfect,
and within 1/10 of a wavelenth is achievable.
http://home.thezone.net/~dbourgeo/feb/foucault.html
So if a 16 foot wide piece of glass is still within millionths of an inch after 60 years, how long will it take for it to deform a visible amount?
I seem to recall reading that the Comets had windows with square corners, which greatly increased the stress on the skin of the plane. Frequent pressurization and depressurization due to commercial flight caused the metal to fail.
Square corners in any material, metal, ceramic, or plastic, create points of 'infinite' stress which can then lead to failure. That is one of the reasons why rounded corners are used in modern commercial jets.
About all materials flowing: I did my undergrad in astrophysics and now work in condensed matter. During my undergrad degree I took some instrumentation classes and apparently the crown glass used to make mirrors in telescopes do in fact "flow" or creep with time as the heavy pieces of glass are tilted for long periods of time. It's nothing you'd be able to see by eye, but even a few hundred nanometers of creep can distort your optical image somewhat and is noticeable. I'm not 100% sure of this, but it seems to be what I remember.
I was mainly poking fun at the "are be" typo, not at metal failure. Sounds like something to avoid, at least until they come up with metal viagra.
These counter-examples are located in regions where gravity has, for much of the time, been a repulsive force. Simple. Egyptian glass has not sagged because there have been roughly equal periods of attractive and repellant gravity.
Sorry, I really want to hold on to this urban myth, otherwise Walking On Glass is ruined.
From Wikipedia:
"In 2004, 3M developed a technique for making a ceramic composed of aluminium oxide and rare earth elements to produce a strong glass called transparent alumina."
See also http://en.wikipedia.org/wiki/Aluminum_oxynitride
It might not be a metal, but it does contain Aluminum and it is transparent.
Funny how certain ceramics start conducting electricity really well when you cool em down to 77 kelvin.
They ARE out to get you simply because They are in it for themselves and they don't care about you.
This is about making non-cristalline, amorphous metals, but TFA does mention that the result is NOT transparent (rather shiny black).
My point was, those who are NOT materials scientists will likely misinterpret the term "metallic glass". In common usage, the noun is interpreted as the subject. In fact, this is a rule of the English language. "Glass" is a noun and thus a candidate for the subject of a sentence. "Metallic" is merely an adjective modifying the noun "glass". So if you really want to be technical, "metallic glass", when referring to something that is basically metal and not a silica product, is just plain incorrect English. This is true regardless of whether materials scientists commonly use that phrase.
Thus in English, "metallic glass" means glass with similarities to metal, but which is not actually metal, whereas an "amorphous metal" must necessarily be some form of metal. (Not an "amorphous" with some properties of metal.) In both examples, the first word is the adjective, the second the noun. This avoids confusion and still constitutes proper English. "Metallic glass", when used to mean a "glass" made of metal, does neither. The proper construction would be something like: glass-like metal.
I am aware that "glass" can mean amorphous (non-crystalline), but the majority of the public likely does not, and improperly switching the noun and the adjective confuses the issue, even for people who know the language only by "feel" rather than the intellectual intracacies.
In summary, my comment was not about the industry-speak but about standard terminology and use of English.
Yeah sure. Alumina, I've seen translucent objects made from alumina. And of course sapphires are made from alumina as well. I'm just talking about pure metals, or materials (like graphite) that conduct like metals.
Bitter and proud of it.