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'Super Steel' Sought For Fusion Reactors
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."
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.
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Popular Mechanics explains this. Not that I think it will matter to the conspiracy crowd.
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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.
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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.
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.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
The jet fuel had almost nothing to do with the collapse other than it was a big match that set everything else on fire. The vast majority of the fuel was consumed in the initial fireaball or within a few minutes of the crash. The critical part was the removal of fire protection and the severing of the sprinkler stack. The solution is a more robust and adhesive fire coating (like foam bead containing cement with polymer binders added to the liquid portion) and redundant sprinkler stacks. NIST estimates the cost increase to be between 2 and 5 percent for ALL of their building code enhancement guidelines including the biggest cost of increase emergency stairwell size. To me this seems like a small price to pay for general emergency preparedness and can most likely be offset over the lifetime of the building through decreased insurance premiums.
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Yes, while it won't melt at the temperatures it was exposed to in the twin towers, it is at less than 50% strength because of the heat.
After a tour I was given of the MIT Tokamak, the professor indicated that the problem with fusion reactors wasn't heat, or even fusion. it was neutrons.
Apprently, the reactor is flooded with neutrons during the fusion 'events', and over time it will turn whatever 'steel' the reactor cell is made of into a porous sponge, that may collapse. If it didn't (maybe engineered to stay standing while highly porous) it would be next to impossible to dispose of the neutron-bombarded material.
He indicated that the ideal material was silicon carbide (SiC). the problem? no one knows how to machine it yet.
the funniest thing he said? I asked him when he thought we'd have fusion reactors. He said (I paraphrase) the he started in fusion energy in the early seventies - we were 25 years from a commercial reactor. now, 30-odd years later, we're 50 years away...
an aside - the tokamak is powered by a mind-bogglingly huge flywheel. several megawatts (i think) awe. some.
1. No steel builing has ever collapsed due to a fire.
The WTC is by a huge margin the tallest man-made structure ever to collapse. There's a huge difference between a 10-story steel building and a 100+ story one.
2. The WTC 7 was not hit by a plane and collapsed, according to NIST 'due to a fire'.
See above. It had significant structural damage from falling debris, which contributed (along with fire) to the collapse.
1. The government explicitly forbit independent investigation of ground zero basically shipping most of the evidence on the site to be smelted - possibly to make the burden of proof on conspiracy theorists to be especially burdensome.
The words "these are facts" should never, ever be followed by the word "possibly."
2. Several witnesses report hearing loud explosions on the WTC before any planes hit.
Okay so if the explosions happened before the planes hit, why didn't the buildings collapse immediately? I thought the bombs supposedly went off after the planes hit and caused the collapse? Were these first bombs duds?
3. The opinions ( not fact, cause I can distinguish between those two ) of many engineers and scientists - none paid by the government, in stark contrast to 'not all paid by' - that it looked the textbook case of controlled demolition.
I'd call it "several." But sure, call it "many" if you like.
4. The 9/11 Comission report didn't even acknowledge WTC 7's existence. In a healthy democracy, that would be as admission of guilt, in my opinion. Since it's obvious that that part of the disaster DID NOT go according to plan.
But you're suggesting that WTC 7 was intentionally demolished with explosives. Which obviously worked. So how did this "NOT go according to plan"? Jesus effing Christ, at least keep your crackpot theories consistent with each other.
I do agree with a previous post I saw which suggests engineered ceramics. Ceramics are very good refractory materials, as they retain much more strength and oxidation resistance at high temperatures than steel, or for that matter, nearly all metals. They're also most likely going to be much, much cheaper than any metal engineered for this application. Steel doesn't fit the bill yet, and it would probably take a lot of research to figure out new heat-treatment methods to get it there. Some more exotic metals like some in the platinum group might look attractive until you see the price tag.