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Transparent Aluminium
Lynx writes "As the german magazine Spiegel reports, scientists at the Fraunhofer Institute for Ceramic Technologies have developed a transparent tile made from aluminium oxide pellets baked at 1200C. The material is very hard, and could be used as bulletproof windows." Use the fish.
Ha! That guy finally figured out those equations Scotty gave to him back in Star Trek IV! Another technological breakthough thanks to good 'ol Scotty.
Yeah. Star Trek IV: The Voyage Home. "How do we know he didn't invent the bloody thing." Looks like it only took the guy 18 years to figure out the "dynamics" of it. Now all we need is dilithium crystals, isolinear chips, and fusion reactors.
...with some transparent concrete to build a transparent house! Now people who want to live in a "glass" house don't have to worry about throwing things at each other! Oh, but they still have to worry about being naked...
Sorry. I should have read the blurb more carefully.
This isn't transparent aluminum; this is a transparent aluminum oxide. That is just not the same thing as aluminum anymore then water is Hydrogen gas, or table salt is the same thing as Sodium metal or Chlorine gas (both very harmful chemicals, sodium can explode when it comes in contact with water, and Chlorine can kill you in a few breaths, yet we eat salt all the time)
And secondly we have known about aluminum based compounds for a long time, in fact, longer then we have known about Aluminum or even about elements in general. Alum, the compound from which aluminum gets it's name (and which we extract aluminum from) has been known to man for ages and is, in fact, transparent.
autopr0n is like, down and stuff.
A whale of an idea!
The first sentance of the second paragraph should read: "And secondly we have known about aluminum based transparent compounds for a long time"
autopr0n is like, down and stuff.
Btw, The artical indicates that this material is 3 times as strong as steal, making it far stronger then pure, regular, opaque, Aluminum metal.
autopr0n is like, down and stuff.
No. He just showed them the molecula structure. He didn't tell them how to manufacture it.
Wouldn't it be nice if schools got all the money they wanted and the army had to hold jumble sales for guns
> this material is 3 times as strong as steal,
No, it says it is three times as _hard_ as hardened steel, which isn't the same thing (though they are related). Considering that corundum (i.e. ruby, sapphire) is made of aluminium oxide, that isn't that surprising.
Forming that hard material into tiles of unspecified but obviously reasonable toughness and strenth while keeping it transparent is the impressive bit.
rant
This would be useful for windows of buses and trains in areas where they tend to get vandalized.
-- Ed Avis ed@membled.com
P.S. Considering the number of people who are confused about the difference between silicon and silicone, it's not surprising some can't tell the difference between aluminium and alumina (aluminium oxide).
(Aluminum/aluminium is just US/international spelling. Looking at the original German article it uses "Aluminiumoxid" where the fish translation has alumina.)
rant
let out a giant yawn.
Alumina being transparent or strong is hardly new. Although the bullet proof glass thing is pretty funny. Alumina is not tough, it may be strong, and even greatly stronger than steel should we be talking about specific strength, but it is not tough at all. And I don't know about you, but the last thing I was between me and a bullet is a sheet of something that will shatter with countless sharp edges to cut me to ribbons.
I'm sure there are a great many chemical concerns that would be thrilled to tell you all about their alumina powders should you care to ask. But trust me, until we can do with alumina what clams can do with chalk the most interesting thing one is likely to do with alumina is make a crucible.
--Jimmy has fancy plans; and pants to match.
I can walk around in public with my aluminum foil hat and not look stupid anymore!
SIG: TAKE OFF EVERY 'CAPTAIN'!!
as Babelfish & Co are not really up to it yet, here's my human-made translation of the German article. I'm a German native speaker, but I can't guarantee the English spelling, so take with a grain of salt ;-).
Things in [brackets] are my remarks.
- - - -
Der Spiegel [leading German magazine, a la Times or Newsweek]
February 19, 2002
TRANSPARENT
Armour-like tile protects from projectiles
Researchers in Dresden [German city] have developed transparent and extremely hard tiles. The Pentagon, among others, is fascinated by this material, which can be used to produce e.g. bullet-proof visors.
[PICTURE] picture caption: "transparent Aluminium tile"
America's weapon technicians show interest for an armour-like tile from Dresden. At the "Fraunhofer-Institut für Keramische Technologien" [Fraunhofer institute for ceramics technologies] there, fine-grained aluminium oxide was successfully baked in an oven at 1200 C to produce an extremely hard, transparent material.
A plate sized 10x10 cm (thickness: 1 cm) only weighs about 400 g, but is three times as hard as hardened [tempered?] steel. During shooting trials on behalf of the "Bundeswehrbeschaffungsamt" [federal procurement office] in Koblenz, "outstanding results" were achieved, according to the researcher Andreas Krell.
The tiles are also being examined in the US state of Idaho: The Pentagon is fascinated by the transparency of the material, which can be used to build bullet-proof visors or big windows for armoured personnel carriers [Panzerspähwagen?].
oooh I wonder what sunglasses made of blue sapphire would be like ?
Expensive.
This is very cool... however it's no more exciting than micrograin metals or some of the amazing things they can now do with micrograin titania.
Micrograin copper for instance conducts like gold, and is nearly as hard as steel (while being much lighter... this is wonderful stuff.)
Micrograin titania, another ceramic, is transparent, significantly harder than steel, as flexible as plastic, lighter than aluminum, and can smile at temperatures that would turn most metals into soup. Some folks who are working diligently on electrolytic extraction for titanium (the process that brought the price of aluminum down, from more precious than gold), believe that micrograin titania could one day make the perfect engine (since it can be cast and sintered directly into useable parts.)
Face it kidlings, the steady march of material science is giving us an incredible boon of new and amazing new stuff to play with... pretty much like the rest of technology knocking on our collective doors. I want to be the first on my block with a Moller Skycar with the transparent titania upgrades.
Moller Skycar; http://www.moller.com/skycar/
Genda B -- I detest Osama bin Laden, a man who is the bigoted, violent, religiously fanatical, spoiled son of a rich oil magnate, who believes he can control the world with the threat of war and destruction. Hey, wait that sounds like somebody else...
Heavy.
Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
Just buy a space shuttle. They all come with them included.
You can actually buy sapphire windows at least up to 15cm square some places I found on the net.. supermarket scanners also sometimes have sapphire windows apparently.
The watchglass of my Rolex is a sapphire crystal. Looks cool, doesn't scratch. This page has info about synthetic sapphire watchglasses. It says Seiko coats mineral glass with synthetic sapphire (sapphlex they call it) to make it hard.
Right!
Oh, wait, this one isn't about computers.. hehe.
My Karma was at 49, then they switched to words. All that work for nothing!
even billions if the practice really takes off in the overpopulated 3rd world
Why is it that the 3rd world is always thought of as "overpopulated"?
FYI the population density of San Mateo County or Manhattan is greater than that of Bangladesh.
How come we never hear of the overpopulation of those places? Is the problem really too many brown people?
The "overpopulation problem" is simply a way for "liberals" to indulge in guiltless racism.
So, that would make those of us in the US at least spelling it the original way =]
What?
Unbreakable beer glass.
As an aficionado of German beer, I'm sure that this will be the first real application. They just want to get the military to pay for some cool toys along the way.
(L. alumen, alum) The ancient Greeks and Romans used alum as an astringent and as a mordant in dyeing. In 1761 de Morveau proposed the name alumine for the base in alum, and Lavoisier, in 1787, thought this to be the oxide of a still undiscovered metal.
Wohler is generally credited with having isolated the metal in 1827, although an impure form was prepared by Oersted two years earlier. In 1807, Davy proposed the name aluminum for the metal, undiscovered at that time, and later agreed to change it to aluminum. Shortly thereafter, the name aluminum was adopted to conform with the "ium" ending of most elements, and this spelling is now in use elsewhere in the world.
Aluminium was also the accepted spelling in the U.S. until 1925, at which time the American Chemical Society officially decided to use the name aluminum thereafter in their publications.
What?
hart (Härte): hard (hardness)
stark (Stärke): strong (strength)
I do speak German, I've read the article, and they're saying exactly what you think they're saying: it's three times harder than hardened steel. Now they just need to make it a bit more transparent and less milky.
There are at least two different ways to think about overpopulation. The first is pure density, so many people in so many square miles. That's what you are talking about.
Then there's the birthrate. I believe the us birthrate is something like 2.0(I could be wrong about the exact figure, but I know the sense is right), which means 2 babies born for every 2 people in the country. Some quick thought will realize that this is not enough for population replacement. The replacement birthrate is something like 2.4 live births for every 2 people in the population, because you have people who die before they reproduce, childless couples, etc. In the past 100 years or so, the trend has been that the the more developed the country is, the lower the birth rate. So while a particular county may have a very high population density, the people there are not reproducting at a rate that can sustain that population. The population is sustained through immagration (hence Buchannan's book where he advocates all the white folks getting busy getting busy and pumping out more white kids.) Generally speaking, the more educated you are, the fewer kids you have.
Plus, San Mateo has enough resources available to feed its population. This is not always the case in what are called 3rd world countries.
So while San Mateo has more people per square mile, those people all have a higher standard of living and their population is stable. They aren't necessarily overpopulated for their geographic area. Meanwhile, in a 3rd world country the population is increasing while the standard of living and education is not.
Personally, I think it wouldn't be a bad idea if a random sampling of half the population of the planet never had kids and those that remained had only 1 or 2 kids. Random would remove all possibility of bias. There are too damn many people everywhere.
pronoblem
> the original name of the element was 'Aluminum', but in England they felt it should follow most of the other elements and end in ium, so they changed it to allow a 2nd spelling
e ments/aluminium/history.html).
In English "aluminium" isn't just an allowable second spelling, it is the standard spelling. It's also the internationally agreed IUPAC spelling. (And yes "aluminum" was used before "aluminium". Full history at http://www.webelements.com/webelements/scholar/el
rant
http://www.webelements.com/webelements/scholar/ele ments/aluminium/history.html says "the name alumium [...] change it to aluminum." which you have to admit is more convincing than "the name aluminum [...] change it to aluminum."
rant
Soon we can protect our computers from drive by shootings! Why, I just lost my third i386 to one last week.
Everytime you look at porn a devil gets their horns.
> It is the second-most hardest substance known to man after the diamond (Vicker's scale 9 to diamond's 10)
p roperties/ text/definitions/hardness-mineral.html
You are thinking of the Mohs hardness scale, not Vickers.
http://www.webelements.com/webelements/
And just because corundum is second on the list doesn't mean there are no substances in the range between 9 and 10. Things like titanium carbide, silicon carbide, boron carbide, and boron nitride are (or can be).
(However they aren't found naturally the way corundum and diamond are).
rant
>
> Now comes some charismatic leader and, well, I hope I'm in the grave by that point.
What, you get pretty fireworks and solve the "too many males and not enough females" problem. Evolution in action ;-)
"It would be more like a ban on covalent bonds between carbon and chlorine, which rarely if ever occur in nature and are stable enough to persist for centuries."
Not really true -- halocarbons are actually more common in nature than you think. A number of organisms such as certain fungi and marine algae produce halocarbons containing chlorine, bromine, and iodine. These compounds can range from simple Methyl-type compounds to polycyclic aromatics.
They can also be formed when wood decays in the presence of halogen salts. The lignin portion of wood is basically a polymer of aromatic alcohols, and under the right conditions halogen ions can react to form aromatic halocarbons.
If you're into that sort of thing, which is most definately cool. You should look at some of the stuff with spider silk. There's a company that genetically engineer goats to express the stuff spider silk is made of in their milk. (one would assume the golden orb spider) Then they get fetta cheese and spider silk on a reasonable scale. (I don't know if fetta cheese comes from goats, but I do like the way it just rolls off the tongue, so if you're a cheese expert feel free to interject).
I would also like to think that our military personel have something a little more substantial that alumina, perhaps silicon carbide, or better yet a ceremet of silicon carbide and nickle (but maybe that'd be too heavy). Either way in a kevlar vest, their opaque and not windows. I think Titanium Boride has been used for bullet proof vests too.
A'ight, yo.
--Jimmy has fancy plans; and pants to match.
How many children a woman has during her life is not really a usefull statistic when trying to determine population growth. It is much more usefull to compare birth and death rates.
According to the CIA Factbook:
Birth rate: 14.2 births/1,000 population (2001 est.)
Death rate: 8.7 deaths/1,000 population (2001 est.)
So for each death approximately 1.6 children are born. This would indicate population growth.
The fact that 2.8 children are born for "every two people" does not tell us anything about population growth. Depending on life expectencies, infant mortality rates and sex distribution of the population that could indicate growth or shrinking.
Si vis pacem, para bellum
The only thing more annoying than a Libertarian is an (un|mis)informed Libertarian
> I'm not sure we can count on accurate of translationedspecific words in article, however...
> I'm not sure exactly what property is the most significant in stopping bullets
Well, the article clearly uses the word "hardness", not "strength" (I do speak German), and given the context in which it is used (research into bullet-stopping materials), I'd say it's pretty clear that the bullet-stopping type of hardness is meant here. If it had the properties of jello WRT stopping bullets, I don't think they'd waste their time on it.
Hardness increases with toughness not necessarily vis versa.
Think of it roughly in these terms:
A hardness contest between two materials consists of trying to scratch one with the other. The one scratched is harder.
A toughness contest between two materials consists of trying to break one material with the other. The one broken wins.
Seastead this.
> The piece of sapphire crystal on my watch is perfectly transparent...
Except you can't buy it in the shape of your car's windshield.
Metals made transparent by photonic layer structure:
http://eetimes.com/story/OEG19991108S0095
This is much more useful than transparent armor,
IMHO, if it can indeed be applied to photonic
band-gap filtering...
> Making one the size of a windshield has got to be prohibitely expensive, though...
Right, and that's the whole point of this research. How to essentially "bake" a sapphire of any size and shape (relatively cheaply, I would also assume).
San Mateo has enough resources available to feed its population.
No, it has the money to buy food and water from other sparsely populated areas in the US. Just disrupt civilization, motorized transportation, or the belief that pieces of green paper are actually worth something, and any American city would be in worse shape than Bangladesh... On the average, the US is fairly lightly populated, but that's averaging farmlands with one family per square mile, deserts and mountains with almost no permanent human residents, and densely populated urban areas together..
This would be used to create a whole new generation of Apple paraphenalia.
The new: iCar!
The exciting: iBoat!
The unbelieveable: iRoof!
The possibilities are endless, with our strong, clear steel!
It's been a long time.
Edmund Optics will sell you sapphire windows, along with tons of other cool stuff. Ball lenses are pretty neat, too.
Again, it depends. The birth/death rate is another way of looking at it, but it doesn't necessarily take into account recent rapid immagration. Or the fact that only a small percentage of people in a population are capable of giving birth at any one time.
Let's say there's an island with 1000 people on it.
If the island is suddenly discovered and a lot of people move in, say 1000 immagrants (50/50 split) are more likely to be younger (say under 50) and so they move in and have children. If the immagrants only have 1 child a piece after moving there, the death rate remains the same or goes up slightly (due to accidents), where the birth rate doubles. But the island's population will not grow that much over time because the new people do not replace themselves.
Fun with statistics!
well, if you remember, isolinear chips didn't come around till star trek:tng. the episode "relics" even brings this up. that's the episode with scotty and the dyson sphere. getting off the transporter pad, scotty asks a question about one of the panels, and giordi says they replaced the old crystal memory cards with isolinear chips. so according to the trek timeline, those are another 300 years off.
wow, i'm a dork
Very common. Any decently good watch has a sapphire face. Why? It's really hard, so it doesn't scratch easy.
;)
My Esquire has one... so did my Luminox...
(Oh.. regarding those Luminox navy seal dive watches..... they are indestructuble, for sure.
Just don't wear one to bed.. I woke up and found one of the prongs that hold sthe strap pin in had sheared right off the main housing. GO figure.
Waterproof to 200 meters, used by navy seals, can take a hell of a beating.. but don't ware it to bed
As bad as it is to reply to something so far off topic (well the thread thereof) that is one of my favorite KITH sketches.
--Josh
There are exactly 42,935,718 letter sized sheets in a square mile.
Strength - A property of materials under elastic deformation, meaning the degree to which the material bends under load, and then springs back to its original shape. At sufficiently high loading, the material deforms plastically, meaning it stays bent. Strong materials deflect very little under load (low strain per unit stress), and can take high loads before plastic deformation occurs.
Toughness - A property of materials that contain microcracks or other fracture-inducing characteristics. Such flaws cause localized increases in stress levels and thereby cause fractures to expand until the material fails catastrophically. This is the mechanism underlying stress-corrosion cracking and fretting fatigue. Tough materials do not have high localizes stress at crack tips, and can tolerate microcracks without catastrophic propagation and failure.
Hardness - The strength of a material at its surface. Measured empircally by poking it with sharp objects. Hard materials resist scratches and dents. But whether they deform (elastically or plastically) has nothing to do with their hardness. It has to do we their bulk strength.
This research facility focuses on ceramic-related activity. Given that I am by profession very familiar with the process involved in the manufacture of such materials, I can venture an interesting guess.
Porcelain and ceramic tiles get their strength from 2 processes: exposure to pressure from a vertical hydraulic press, and subsequent firing (baking) of the tile.
1200 degrees is not very far off the temperatures at which the firing curves for commercial mass produced porcelain lie.
I thus assume that the difference lies in the pressure at which the pellets are pressed. It's got to be a LOT higher than the pressures used in the commercial porcelain/ceramic manufacture environ.
And anything will become harder when you compact it. Look at how diamonds are formed.
So essentially, what we are saying here is " Hey, we took some transparent stuff, compacted it really tight then fired it, and whee, we got ourselves a slab of very hard transparent stuff"...
Where's the innovation?
Blearf. Blearf, I say.
"harder" should, of course, have been "less hard".
Seastead this.
Nonsense! Everybody knows that the nudity taboo was invented by Gapchaneloren IX in 1000 BC in order to help out the garmet industry!
If the material is close to 100% of solid density, then you can put a polymer between a couple of layers of it, just like safety glass. One reason this is big news is that alumina is cheap and available by the tonne. Then again, so is silica.
Good read but It really doesn't explain how you could use it to say.....
..build a million gallon tank on a starship to transport two humpback whales 200 years into the future in a desperate attempt to save mankind from a strange monolith emitting beached whale sounds.
Jesus....what ever happened to investigative journalism these days? Also, wasn't this guy supposed to speek english?
-Chris
--an unbreakable toy is useful for breaking other toys--
Great.
But we already have bulletproof glass. What's so special?
For a ceramic, Alumina is pretty tough, but that's like saying for a 5th grader Todd Peterman is pretty tough. It takes very little to propigate cracks through ceramics. There some stuff that can be done, but ceramics aren't metal. And alumina has always been transparent.
Now this MIGHT be news if they some how got their alumina powders on a nano scale where the alumina crystal grains are smaller than the wavelengths of light, then you'll actually get a relatively tough, and see through material. Not be cause something magical happens on that scale, but because the crack length will be huge, and actually require the formation of a large surface which would take a lot of energy despite the low toughness of the alumina. That would be news. BIG news. At least to me. But that's not what they said.
They said they made a 10cm alumina tile. Big whoop.
They might be able to enhance it by making it like corning wear, but that summery of a press release was clearly too light to provide that kind of detail. Which might have been interesting, although not news.
I would bet that it being transparent means they either used a spectacularly fine powder, or it is basically fully dense as there doesn't appear to be many internal surfaces to scatter light (ie it's not opaque).
Further more, I would bet that the flaw(s) introduced by the bullet would not be what caused it to fail, I would bet that pre-existing flaws near the bullets point of impact would be vastly expanded. Worse yet, the alumina tile might even bounce the bullet off instead of just stop it.
Maybe the news is the simplicity and low cost? Too bad that didn't make it into the news then.
Either way it sounds like it's nothing but a press release for a non-large company that's really happy that they might picked up as a contractor for the Department of Defence.
Yawn. Already, we've given it more consideration that it deserves.
--Jimmy has fancy plans; and pants to match.
> moissanite
:)
(fx:googles) Oh. Ok, I take back what I said about it not being found naturally.
I actually don't know whether moissanite is natural or not.
I always assumed it was synthetic.
So I wasn't trying to make a point or anything with that post...I was just proud of myself for remembering the name for silicon carbide