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Laser Turns All Metals Black
Posted by
Zonk
on Thu Nov 23, 2006 09:40 PM
from the bzoooom-whaaaawwwww dept.
from the bzoooom-whaaaawwwww dept.
Roland Piquepaille writes "Researchers at the University of Rochester have found a way to change the properties of almost any metal by using a femtosecond laser pulse. This ultra-intense laser blast creates true 'black metal' from copper, gold or zinc by forming nanostructures at the surface of the metal. As these nanostructures capture radiation, the metals turn black. And as the process needs surprisingly low power, it could soon be used for a variety of applications, such as stealth planes, black jewels or car paintings. But read more for additional references and a picture of this femtosecond laser system."
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anything special? (Score:4, Insightful)
Re:anything special? (Score:5, Funny)
Hint: Think "perfect stealth", not only for planes, but for your car as well. Make that cop toting the radar gun go insane.
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Special Properties (Score:5, Funny)
Well, that one property alone makes it excellent for building Ford Model-Ts.
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Re:anything special? (Score:5, Interesting)
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Re:anything special? (Score:5, Informative)
No, because if it was invisible you'd be able to see what was behind it; if it merely absorbs the light that falls on it, you'd see a black shape instead...
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Re:anything special? (Score:5, Funny)
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Re:anything special? (Score:5, Funny)
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Re:anything special? (Score:5, Funny)
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"true 'black metal'"?! (Score:4, Funny)
This ultra-intense laser blast creates true 'black metal'
Rubbish, true [youtube.com] 'black [youtube.com] metal' [youtube.com]
(sniff... brings back memories of seeing them in '83.)
How black is it? (Score:5, Interesting)
-jcr
Re:How black is it? (Score:5, Funny)
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Re:How black is it? (Score:5, Informative)
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Re:How black is it? (Score:5, Funny)
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Picture (Score:5, Funny)
I really should just go to bed...
DugUK
black (Score:5, Funny)
Meh (Score:5, Funny)
Space-age technology! (Score:5, Funny)
*bows to Mr Adams*
black... (Score:5, Funny)
(and silver, and bronze..)
That's not all (Score:5, Funny)
This is a big deal for fuel cells. (Score:5, Insightful)
This technology has huge ramifications for chemical reactions that need a catalyst, and also in the area of fuel cells.
Unlike Roland, I actually try to link to the article and not some empty blog. Roland, your technology trends suck. Link to the originating article you fool!
Physorg [physorg.com]
Also, does Roland even have a degree in science? Because he sure doesn't ever seem to have a grasp of the important things in the articles he submits.
You realise what this means, right? (Score:5, Funny)
Nothing to see, move along. (Score:5, Informative)
Hit things with enough laser fluence and the surface atoms will move around, and may even be blasted off of the surface. This is the basis of a standard materials synthesis technique, pulsed laser deposition (PLD) [wikipedia.org]. Hit a target with a laser, and collect the ejected material on a nearby crystal.
Anyone who has done PLD knows that the surface of the target gets rough when you blast it. If the target is a metal, and the roughness is smaller than the wavelength of light (nanoscale), it will absorb light - it will be black.
In any case, the article asserts that the "blackness" is a material property and is therefore permanent. Nonsense. Touch it and the surface particles will rub off, leaving behind a shiny metal surface. Further, I'd be extremely surprised if there weren't tons of existing patents on surface modification by lasers. There are certainly tons of academic publications on the topic.
Re:Blackness (Score:5, Interesting)
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Re:Blackness (Score:5, Funny)
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Re:Blackness (Score:5, Interesting)
For those having difficulty reconciling the "entire power output of the US from a standard AC outlet" thing, understand that you are radiating for a ridiculously short period of time, so you can get a very high peak power in that pulse while still having a very low average power usage if you can unload a decent percentage of the entire duty cycle's worth of power in that one pulse. The Nd:YAG machines that I worked with were only 90 watts or so CW (continuous wave), but when you cranked the Q-switch down to a low enough rate, you could get a peak power in excess of a quarter-million watts in each 10 microsecond pulse. 10 microseconds is 10 *billion* times longer than a femtosecond (same comparison: one second to 317 years), so you have the possibility of having staggeringly large peak powers in these really short pulses.
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