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'Super Steel' Sought For Fusion Reactors
Posted by
samzenpus
on Thu Sep 11, 2008 06:57 AM
from the everything-melts dept.
from the everything-melts dept.
Smivs writes "New research shows how
steel will fail at high temperatures because of the magnetic properties of the metal.
Scientists say an understanding of how the Twin Towers collapsed will help them develop the materials needed to build fusion reactors.
The New York buildings fell when their steel backbones lost strength in the fires that followed the plane impacts.
Dr Sergei Dudarev told the British Association Science Festival that improved steels were now being sought.
The principal scientist at the United Kingdom Atomic Energy Authority (UKAEA) said one of the first applications for these better performing metals would be in the wall linings of fusion reactors."
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If it doesn't work... (Score:4, Funny)
...it will be only the third time that fire has melted steel.
Re:If it doesn't work... (Score:4, Funny)
Yes, this is could be.
The Twin Tower is built like a metal tube. So if it fails, it should fail in dignity, fail like a metal tube. But on that mighty day, PUFF (note: not flame). A metal tube turned into a pile of crackers.
Hell, tensile strength, bending moment, grain boundary, finite element... all thrown out of the window, because it was hit by black magic.
Where is my toad?
Parent
No magic involved (Score:4, Funny)
What do you mean, 'black magic'? A tube can be filled and if it is filled, when you fly your plane in, it gets in line and it's going to be destroyed by anyone that puts into that tube enormous amounts of fuel, enormous amounts of fuel.
Parent
Re:If it doesn't work... (Score:5, Insightful)
By what measure?
1) They got reelected.
2) Their friends got lots of money from the Iraq war (which had little to do with 9/11, but they still managed to attack Iraq anyway). When you have stuff like 1 billion of _cash_ just go missing, it makes you wonder doesn't it? A billion here and there, it all adds up to trillions.
3) What are the odds the "inept" Gov gets elected back in? If people can honestly say less than 30% then sure the Gov is inept, otherwise guess who really are the inept ones?
Perhaps you're assuming the leaders of the US Gov are working for the USA.
Who is a bigger enemy of the US people? The US Gov or the Al Qaeda? Who has cost the USA more, and caused more damage?
Parent
Re:If it doesn't work... (Score:5, Informative)
Popular Mechanics [popularmechanics.com] explains this. Not that I think it will matter to the conspiracy crowd.
Parent
Re:If it doesn't work... (Score:5, Informative)
Yeah. The Twin Towers should have toppled over, but instead, they blew up like a building that was being imploded for demolition.
It figures that today of all days would bring out the conspiracy theories. So you're saying that a building weighing probably millions of tons could topple over a specific and single pivot point?
Also, the melting point of the steel used in the Twin Towers is actually about 400 degrees HOTTER than the temperature at which jet fuel burns.
If the jet fuel is out in the open, where heat can dissipate, that would be true. But this was a whole LOT of fuel in an enclosed space, so as the fuel burnt, the steel could keep getting hotter and hotter. Burning fuel = energy released. If the energy cant escape, it builds up in the form of heat.
The Twin Towers would also be the first example in history of a steel building where the steel failed due to fire.
And the thousands of tons that slammed into it at high velocity had nothing to do with it? (Actually, I'm guessing that had something to do with it, but not sure.) If you're spinning theories here, you need to stick to WTC building 7, the collapse of which was thoroughly studied, and concluded that fire alone was the result of it's collapse.
Parent
Re:If it doesn't work... (Score:5, Informative)
And the thousands of tons that slammed into it at high velocity had nothing to do with it?
NOVA recently did a special about this. Apparently the NIST investigation concluded that the impact of the jets stripped away a lot of the fire-proofing material that should have protected the steel.
Once the steel was exposed to all that heat it was only a matter of time before it failed. It never melted either -- it became flexible and eventually failed as a result.
Parent
Re:If it doesn't work... (Score:4, Informative)
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Re: (Score:3, Insightful)
Yeah, they had a neat animation that showed how it failed.
Basically the support beams for each floor started to sag as a result of the heat and the load that they were supposed to carry. As they sagged they pulled the outside walls (where most of the support for the building was) further and further inwards. Eventually the outside walls failed and the floors started to pancake onto each other. Once all of that kinetic energy was released there really wasn't a way to stop it -- hence the failure of the wh
Re: (Score:3, Insightful)
Well, first I'd ask you for a citation (preferably one with pictures and/or video) because I've never heard that.
Re:If it doesn't work... (Score:5, Informative)
Parent
Re:If it doesn't work... (Score:5, Insightful)
Yeah. The Twin Towers should have toppled over, but instead, they blew up like a building that was being imploded for demolition. Also, the melting point of the steel used in the Twin Towers is actually about 400 degrees HOTTER than the temperature at which jet fuel burns.
In Oakland CA, a tanker truck carrying gasoline crashed under an overpass crashed [sfgate.com] and burst into flames. (Everyone was OK) The heat from the gasoline caused the metal in the overpass to weaken and the whole thing collapsed.
This pretty much proves that burning fuel can cause metal to weaken and a structure to collapse. This is especially true when you consider that jet fuel burns hotter than gasoline.
The Twin Towers would also be the first example in history of a steel building where the steel failed due to fire.
Maybe so, but it happened. Other examples would be the one I listed (although not a building) and WTC7.
In other words, "Truthers" are full of shit. They've been debunked countless times and they keep coming back. Accept it, you are wrong. There is no government conspiracy. There was no demolition. Terrorists hijacked planes and flew them into buildings where the heat from the fires caused them to collapse. That is FACT!
Parent
Re:If it doesn't work... (Score:5, Insightful)
"Truthers" are afraid of facts because they don't conform to their own paranoid world view. Simply put, they want the gubmint to have conducted some wildly over the top, physically impossible plot of some kind and they aren't going to let a mountain of evidence that says different get in the way. This is why they spend their lives poring over minute inconsistencies, similes, misquotations and so on.
The funny thing is you can state very clearly to a "truther" why steel doesn't have to melt, or how fireproofing is rated by the hour, or provide evidence of how other steel frame structures fared after fire and the morons will still bleat the same shit all over again.
At this stage I think it is okay just to mock them openly to their face. They belong in the same category of stupid that creationists and holocaust deniers occupy.
Parent
Re:If it doesn't work... (Score:5, Insightful)
> The Twin Towers would also be the first example in history of a steel building where the steel failed due to fire.
Err... steel fails in fire all the time. It's a very common event... to the point that fire fighters have hated steel constructions for the better part of a decade.
Ooo, there's even a wp thingy on a recently famous example of a department that didn't comprehend that steel can and will fail.
http://en.wikipedia.org/wiki/Charleston_Sofa_Super_Store_fire [wikipedia.org]
I think part of the confusion stems from the fact that these newer structures are held together by math... not mass.
The history of steel as a "massive" construction element makes people think that a steel truss construction will rival the failure mode and resilience of the old, truely massive, heavy timber constructions... or at least inherit some of the legacy of something "massive". It's freakin STEEL, man!
But it isn't true - trusses work because of math, not mass. The failure progressions are totally different than the evolutions of old (most notably, there often is no progression; one element fails, the entire assembly fails simultaneously.)
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Re:If it doesn't work... (Score:5, Interesting)
I recall that the church where I grew up used huge laminate wooden beams to support the roof. We asked our pastor why they'd used wooden beams instead of steel beams. He responded that the laminate wood beams were actually stronger than steel in a fire, because the steel would weaken (not melt) in the heat and wouldn't support the roof for long. Laminate beams, OTOH, had been shown to hold their strength for hours in a fire - taking up to 24 hours to burn all the way through. (And of course, the wood beams look a lot nicer than steel.)
You've been out-engineered by a Lutheran pastor from the 70's.
Parent
Re:If it doesn't work... (Score:4, Insightful)
Heavy timber and large engineered wood members generally do survive fires better than steel, at least from a structural sense. The beams can burn, but wood is a pretty good insulator, so while the outside of the beam might be charred black, there's still plenty of sound material left in the middle to hold the building up. Structure in buildings are generally specified with a very large safety margin. There's more than enough wood there so that you can afford to lose some of it to a fire. Steel, on the other hand, conducts heat very well, and so the heat required to weaken it moves throughout the member quickly. The fire doesn't have to work through the steel to weaken it, it can basically attack it all the way through all at once.
I've been in a number of buildings in the french quater in new orleans that are over 100 years old, and which have been through a number of fires. Many of those buildings contain beams that are black with char all around, but have continued to support their roof for decades.
There are a lot of reasons why steel is used instead of wood. There are many ways to protect steel from fire damage, and even with those measures, steel will often be significantly cheaper than wood. There's often a lot more flexibility with steel, as you can get a far wider variety of shapes than wood.
And just FYI, building structure is designed by structural engineers, who generally come across as pretty intelligent. Mechanical engineers (in building design at least) design HVAC, electrical, and plumbing systems. Overall, I've been far less impressed with their skill and enthusiasm compared to structural engineers.
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Up Next (Score:4, Funny)
Re:Up Next (Score:5, Funny)
You'd invent more stuff if you used your computer mouse instead of talking to it.
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Re:Up Next (Score:4, Funny)
A keyboard? How quaint.
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We've learned something new about 9/11 (Score:3, Insightful)
Would the fact that we've learned something new about steel thanks to the way the Twin Towers fell, silence the conspiracy lovers?
No, of course not. What the hell was I thinking there?
It's Certainly a Strange Coping Mechanism (Score:5, Interesting)
Would the fact that we've learned something new about steel thanks to the way the Twin Towers fell, silence the conspiracy lovers?
No, of course not. What the hell was I thinking there?
Well, we're getting WAY off topic from the original story here but people deal with loss differently. Some Americans have a near psychotic desire to be a part of bringing justice to those responsible. 9/11 affected us all in different ways. From losing loved ones to losing a sense of security to losing our rights, everyone believes they've lost something.
I listened to a This American Life episode where a man whose mother was raped and killed spent a large part of his life going over what had happened. He even went so far as to go to the jail and interview one of the murderers. He was so convinced there was more to it than just a random robbery gone wrong.
The "Truthers" (as they call themselves) are trying to cope with this in a unique way where they will relentlessly seek the truth--to a fault. They won't ever be satisfied because the attacks were so inconceivable that there must be an equally outrageous explanation for them. Occam's Razor is not in their reasoning kit anymore.
Personally, I think we just need to let them have their community and leave them alone and give them the information they need. You can't change the way these people think and as Americans they have this right to believe what they want--so long as they don't go infringing on other people's life, liberty & pursuit of happiness.
Following World War II, the public's imagination has gone wild from JFK's assassination to 9/11. It's simply something that can no longer be avoided.
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Re:It's Certainly a Strange Coping Mechanism (Score:4, Insightful)
As always, conspiracies are just a conspiracy to get people to believe in conspiracies. Did you know 9/11 wasn't an inside job?
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Re:It's Certainly a Strange Coping Mechanism (Score:5, Insightful)
Nonsense. The "truthers" are not seeking the truth in any way, shape, or form. All they are "seeking" is ways to warp the facts beyond recognition to support their neurotic preconception.
Seeking truth is what science and religion are about. They have different ways of judging it. I suppose one could make the case that the truthers are a bizarre, benighted, and perverse form of cult, but they are in no sense scientists.
Parent
Re:It's Certainly a Strange Coping Mechanism (Score:4, Funny)
No, just an extremely rare "pleased" variation of the species: Grammaticus patriasocialis gauisus. These creatures have not often been studied by mankind, as they tend to evaporate when exposed to television, billboards, and ninety-nine percent of the American public. Their breeding habits are unknown, and their size and shape can vary dramatically. Since they frequently are seen to inhabit the lofty realms of thought without visible means of support, it can safely be concluded that they are weightless.
Parent
Re:It's Certainly a Strange Coping Mechanism (Score:5, Funny)
Not quite... scientists have postulated the existence of the Pedant's boson which would give them mass (as opposed to weight).
They plan to build the Large Grammar Collider which will fire a stream of apostrophes at near light speed and create scores of sub-punctuation particles, one of which may prove to be the elusive Pedant's boson .
Parent
you have a funny concept of intolerance (Score:4, Insightful)
what gays and lesbians want is the right to be gays in lesbians. what gays and lesbians do in the privacy of their own homes in no way affects you whatsoever
meanwhile, to deny what gays and lesbians want, that is, to be themselves, is "cramming down their throats", as you so homoerotically describe, the beliefs of fundamentalist christianity
in other words, to give gays and lesbians what they want doesn't negatively affect your rights and freedoms whatsoever
meanwhile, to give fundamentalist christians what they want dramatically infringes on the rights and freedoms of gays and lesbians
so you are angry that gays and lesbians do not tolerate your intolerance?
fine
but the idea is more rights and freedoms for everyone... except the right and freedom to deny someone else their rights and freedoms. understand that discrepancy?
what you want is intolerant. so to deny you is not intolerance of you. because intolerance of intolerance is not intolerance. in fact, intolerance of intolerance is pretty much a good definition of tolerance
what gays and lesbians want does not hurt fundamentalist christianity at all: you are 100% free in a world of gay and lesbian rights to continue being an asshole
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Re: (Score:3, Funny)
So by your logic I'm also "removing the rights of christians" if I could engage in pre-martial sex?
There, fixed that for you :]
Re: (Score:3, Funny)
Hahahaha, touche :)
Re:We've learned something new about 9/11 (Score:5, Insightful)
I must apologize for not responding to the main of your argument, but in truth I have no quarrel with most what you say. The point at which I take exception is your reference to the destruction of the World Trade Center buildings as an act of war.
The attacks of 11 September 2001 were criminal acts, not a deliberate attack by a sovereign nation. They were not accompanied by a declaration of war, and there is no reason to believe that any sovereign nation was involved in the planning or execution of these attacks.
The terrorist attacks were a monstrous crime, truly an enormity. However, they can no more be considered an act of war than the Oklahoma City bombing in 1995.
That we, the citizens of the United States, have allowed these to be a justification for a much more costly and brutal conflict is a thousand times more abhorrent. Indeed, it is tens of thousands of times more vile, for we have killed tens of thousands more people in Iraq and Afghanistan than were harmed in the attacks here.
It is generally agreed that the overall course of human history has been one of progress from barbarism to civilization. Let us not now desert that course! We cannot undo the terrible evil that has been caused by our complicity, but let each of us strive to end this war, so that we may begin reparations for the depravity that has been done in our name. For I believe it to be true, that we shall not regain any rights that we do not deserve.
-T
Parent
They Should ask Thulsa Doom how to make it strong (Score:4, Interesting)
"Steel isn't strong, boy. Flesh is stronger. Look around you." Thulsa motions to some of the thousands of followers surrounding his mountain who worship him as the mouthpiece of Set. He points up to the top of a cliff, "There, on the rocks, that beautiful girl." He motions to the girl, "Come to me, my child." The girl steps off the cliff and falls to her death. "That is strength, boy. That is power: the strength and power of flesh. What is steel compared to the hand that wields it? Look at the strength of your body, the desire in your heart. I gave you these...."
Re: (Score:3, Funny)
Current record holder (Score:4, Informative)
The highest performing 'steel' currently seems to be what's called '"maraging steel', but calling it steel seems a bit odd since the alloy contains next to no carbon.
Tungsten is a lot tougher than just about any steel, and it's often used the coating alloys of for example drill bits used in industrial CNC applications.
The point of this article eludes me.
Re: (Score:3, Informative)
Sorry, tungsten (pure) is not very thought. You can drill it and cut it with standard tools. Tungsten-carbide alloy is really thought.
I know because pure tungsten is used to stop radioactivity (it's 50% better than lead), and I work on that field.
Re:Current record holder (Score:5, Informative)
The point of this article eludes me.
You aren't the only one. If you want something that can retain it's strength at high temperatures, don't use steel. I recommend some sort of engineered ceramic, [wikipedia.org] like tungsten carbide [wikipedia.org] (which I believe is what you meant).
The article seems to ignore the fact that engineers see steel becoming weaker with heat as a benefit. If steel was always super strong at any temperature, how would you make anything out of it? Engineers currently utilize the "irregularities" (we call them dislocations) in steel to manufacture things. One such process is known as work hardening. [wikipedia.org] When certain materials, like steel, are formed (bent, rolled, etc.) at low temperature, the dislocations propagate and move. The dislocations interact with each other, like tangling up a ball of yarn, making the material stronger. The component can then be heated to make further manufacturing easier, or left in it's cold worked state to make the finished part stronger. This property of steel is utilized around the world to make very strong, and inexpensive parts. A variety of other heat treatments [wikipedia.org] are available to perform similar tasks.
In summary, the thermal properties of steel are considered a asset, because it allows us to manufacture things with high strength inexpensively. Using a material that is strong at all temperatures will increase costs. Such materials do exist but steel isn't one of them.
Disclaimer: If you find anything above factually incorrect, I was a C student in material science.
Parent
Re:Current record holder (Score:5, Informative)
What you say is largely true, but for nuclear applications you usually have a few more constraints that make steel look more attractive again.
The core of a fast breeder reactor, or the structural components of a fusion reactor, will unavoidably be exposed to a very intense flux of high energy neutrons. These neutrons can cause all kinds of defects in the material you use, ranging from dislocating atoms to changing their elements due to nuclear transmutations, and whatever material you use must be able to withstand the irradiation. Many nickel alloys fail for this reason.
Also any material which absorbs a lot of neutrons, or reduces their energy, is going to cause issues. If you use Nitrogen in a ceramic it may need to be enriched to prevent excessive Carbon-14 production as an example. Some elements, like Lithium, Cobalt and Bismuth, produce very troublesome radioactive isotopes when irradiated. Carbon is quite good, and carbon based ceramics are heavily researched, but it is a rather light nucleus, and will slow neutrons that scatter against it. This may be desirable in a thermal reactor, but for fusion reactors and fast breeder reactors you want a very high neutron energy to enable the destruction of long lived waste isotopes, and this means you need to limit the amount of carbon present in your core and structural materials.
Furthermore materials to be used for a reactor need to go through very time consuming and thorough testing program , and this is why steels are very attractive candidates since much of the necessary data already exists. Sure, using something like Silicon Carbide may be worth investigating ( and it is indeed being investigated for a number or reactor designs ) , but even thou it has good thermal conductivity, corrosion resistance and thermal stability, it is not immediately clear that it will withstand the radiation environment, it's fracture hardness is less than ideal, and you need to be able to reliably produce it to the strict standards required by the nuclear industry. To develop and test a material for nuclear applications is a very expensive procedure, so if you can use materials that you already have data for, it will dramatically reduce the necessary research and development costs.
Also, as usual there is a cost issue of the material itself. Tungsten, with its high melting point, good strength at elevated temperatures, and low neutron absorption is very attractive from technological aspects, but building an entire reactor from it will hurt your bank account.
Parent
Irony if this works. (Score:5, Interesting)
If it worked and we can make Fusion Reactors. This would leave some irony to the terrorist.
The Terrist may think they won because once we go Fusion we won't need to protect our oil interests thus mostly ignoring that area of the world, except for the occasional humanitarian mission, thus reducing our influcene in their countries...
However because we are not funding those countries with money they end up bankrupt in far more trouble then with the US involved.
When the Terrorist actually win they loose, because their goals will lead to their destruction.
Don't get it from UKAEA (Score:5, Funny)
Good LUCK! (Score:5, Interesting)
It is not as if high strength hasn't always been sought after in steels (iron-carbon alloy). INcluding high temperature strength. The usual solution is various nickel alloys starting with the austenitic stainless steels and going up from there (HK-40, HP modified).
Yes, we may yet find some interesting corners on phase diagrams, especially via combinatorial chemistry and high-throughput experiementation. But please do not pretent this search is anything remotely novel.
For many high temperature applications, the usual solution is cold wall designs with refractory (insulating alumina) linings keeping the load bearing steels cool. With or without a (thermal expansion problematic) liner (usually austenitic SS) as a membrane seal.
Steel not the only material out there... (Score:5, Insightful)
Steel is used so widely, in large part, because it's cheap... Iron is one of the most abundant elements on the planet. Many other materials exist that are stronger than steel, lighter than steel, handle MUCH higher temperatures, etc., etc.
For a fusion reactor, however, "cheap" isn't going to be all that important... More exotic materials that can better handle high temperatures would be easily within reach when you're able to generate that much power.
The article completely fails to explain why we, for some reason, MUST use some (not-yet invented) form of "steel" for the walls of fusion reactors. Boron Carbide, Tungsten, titanium, etc., sound like much better options for this application. While this article sounds like a flimsy excuse to exploit this anniversary.
Re:Steel not the only material out there... (Score:4, Informative)
Actually iron is less abundant than aluminum, but it has the advantage of being readily mined, refined, and made into structural steel.
The earth's crust is 61% silica, 16% alumina, 7% rust (iron oxide component of iron ore), 6% line, 5% magnesia, and 5% other stuff. The reason aluminum alloy does not predominate in the structures we build has more to do with the difficulty of smelting, refining, alloying, and heat treating it than its suitability. The mirror image is the great ease of producing ready to use steel I-beams from raw iron ore.
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Mythril (Score:4, Funny)
Re:Mythril (Score:5, Funny)
The fusion reactor in MY house is built from SOLID UNOBTANIUM.
Parent
First invent your fusion reactor (Score:5, Insightful)
I'm confused. Would steel even work? (Score:3, Interesting)
Aren't the magnetic fields in a Tokamak pretty intense? As in, you wouldn't want something ferromagnetic inside?
I thought the leading candidate was vanadium, for its low neutron capture cross section and quickly decaying activation products.
Re:shameless (Score:5, Insightful)
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Re:shameless (Score:4, Interesting)
I disagree. I think it would be the most wonderful irony if a crucial piece of the technology required to provide humanity with a cheap source of energy came from their attacks. The only reason the theocracies in the middle east have any power is that they have a natural resource that the rest of the world needs. With commercial fusion, this evaporates (you can make oil for plastics from air and water if you have enough cheap energy).
Or would you rather that their deaths only benefited Al-Quaeda?
Parent
Re: (Score:3, Insightful)
The 9/11 connection is just a PR plug, though -- those properties of steel have been known for a long time. (I can't guarantee they were known when the building were built, but certainly they were known prior to the event.)
Re:shameless (Score:4, Interesting)
No it didn't. Oh, the land existed, and the House of Saud existed, but the entity we call Saudi Arabia exists solely because of the oil under their feet
Saudi Arabia gained it's modern borders in 1932. Oil wasn't discovered until 1939. It wasn't actively exploited until the late 40s due to WW2. You can argue that oil helps prop them up but the idea that we created these theocracies to get that oil strains creditability when they existed prior to the discovery of that oil.
Furthermore, blaming the United States as the GP did doesn't tell the whole story either. The United States didn't draw the lines on the map in the Middle East. The French, British and Turks did. The United States didn't conspire with Israel to seize the Siez Canal -- the French and British did. The United States never invaded Iran -- but the Russians and British have.
Our hands aren't clean by any means but this knee-jerk anti-Americanism that places all of the blame at our feet doesn't even survive a casual reading of history.
Parent
Re: (Score:3, Insightful)
"bit shamefull to abuse this day, on which the world remembers the victims of this horrible disaster to make these statements how usefull it could be for science."
Every such calamity is worthy of study, because we learn things we do not expect and might miss otherwise. Had the Twin Towers been an accident instead of murder, their study would have been just as important (but with less emotional baggage).
Re: (Score:3, Funny)
I think it was the contents of your head that imploded.