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Laser Turns All Metals Black
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."
Does this black metal have any special properties aside from being black? The article mainly talks about other ways of making it black not being as good- is that all this really does?
This ultra-intense laser blast creates true 'black metal'
Rubbish, true 'black metal'
(sniff... brings back memories of seeing them in '83.)
Trolling is a art,
Are we talking like optical black, suitable for coating the insides of instruments like telescopes and microscopes?
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
Picture can be found here
I really should just go to bed...
DugUK
and his additional references
"wall outlet" ease of the use + "it would drill a hole through your skin" = ultimate home security system
a black engagement ring? perfect for your goth bride! Buy One Now!
Since it's the holiday, the usual rants against the article submitter, Roland Piquepaille, have been rather muted. To sum up:
* He gets a lot of articles posted to the front page, which makes the rest of us jealous.
* His articles tend toward pseudoscience, or at least towards the sort of flashy, headline-inspiring science that does little to advance human knowledge.
* He used to link to his personal blog, which really irritated people who'd love to have their own blogs get Slashdotted on a regular basis.
* He now links to his zdnet blog, which really irritates people who'd love to have their own blogs get picked up by a big corporate website.
* To top it all off, he's French, so all the right-wing nutters hate him automatically.
My irritation comes mostly from the second point -- and, I'll confess, the first as well. But as his defenders (and even the Slashdot editors) have noted, it's not like he's got some inside line to CmdrTaco's desk. He just finds himself at the right place at the right time.
Nonetheless, I recommend continuing to tag his articles with "pigpile", just so's we can keep up.
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
It is, but it also insulates a bit. If you paint something black, it emits and absorbs radiant heat with the properties of the paint, not the metal. This is about making the metal itself black so it absorbs/emits more efficiently.
If my call is important, why am I talking to a recording?
We all know that true black metal is Mayhem.
*bows to Mr Adams*
black is the new gold.
(and silver, and bronze..)
Seems like the perfect coating for solar panels for hot water. The search has always been for the best heat absorbing surface. This type of coating should be the most efficent coating for heat absorbsion.
They found on the way that by using a nanosecond laser they produced Emo metal, which can cut itself.
Task Mangler
Does this black metal have any special properties aside from being black?
Well, that one property alone makes it excellent for building Ford Model-Ts.
When our name is on the back of your car, we're behind you all the way!
So this could make for more efficient thermal solar panels.
When our name is on the back of your car, we're behind you all the way!
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
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.
Samuel L. Jackson can star in the next Terminator movie.
I object to that article, and to the next reply.
I see a red door and I want it femtoblasted black....nope, you're right, doesn't scan.
All available data suggest that regardless of any of this, the sun will still come up tomorrow.
For many, many years we've been able to use lasers to spot-anneal metals, which produces a very dark (though not totally black) mark on the metal while introducing no change at all dimensionally. One area where this process gets used quite a lot is in artificial limbs/implants where the foreign body to be introduced needs to be permanently marked for identification but can have absolutely no sharp edges or anything else that might irritate or damage the tissue. This new process sounds like something similar, although the femtosecond laser angle is kind of new. I'm curious to see how practical it turns out to be, as the few femtosecond lasers I've worked with were *extremely* sensitive to temperature changes.
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.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
This "technology" is nothing new. Just a prof trying to make something mundane sound flashy.
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). 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.
That's just the reflective layer. If the laser in your CD-R had enough power to burn more than just the dye in FRONT of that reflective layer, you'd have some serious issues... ... dummy.
the reason that the stealth aircraft with the radar signature of a small bird isn't seen is because if the radar system could see the signature of the aircraft, then it could see the signature of every small bird within the range of the radar system, which is quite a lot. and a single radar pulse is not capable of detecting speed, you need multiple radar pulses to detect speed. it's like being in a dark room with a strobe light. you can tell how fast an object is moving by gauging the distance the object has moved between flashes. going back to seeing the signature of every small bird, on the radar screen it is impossible to tell where one bird has moved to, since there are 129,600 possible general directions it could have gone. not to mention that birds frequently drop below the radar level, while other birds rise into the radar, and, birds, somewhat like stealth aircraft, don't carry transponder systems
there are 10 types of people in this world; those who get this joke, and those who don't