Pop quiz, Viktor

Pop quiz, Viktor According to my favorite website ever, StatCounter, somebody from Australia found this site by Googling the phrase what happens when you rapidly cool hot metal?. Well, thats what Ive been asking for a while now. Turns out that there is no page on the entire internet that scientifically explains exactly how the climax of Fantastic 4 works. So, to rectify this, I decided to take matters into my own hands and e-mail Professor Christoper A. Schuh, an associate professor of metallurgy in the department of materials science and engineering (Course 3). Date: Tue, 2 Aug 2005 17:06:10 -0400 [08/02/05 17:06:10 EDT] From: Sam Maurer To: Professor Christopher A. Schuh Subject: Metal cooling question Dear Professor Schuh, I am an MIT undergrad in chemical engineering and I have a question that none of my friends in Course 3 have been able to answer. In the movie Fantastic Four, the heroes face a villain whose body is described as an organic-metal alloy harder than titanium and stronger than diamond. To defeat him, they heat his body to supernova temperatures of 4000 K, which has no visible effect upon him, and then spray him with water from a fire hydrant. This completely immoblizes him and also neutralizes his powers, which involve firing electricity from his hands. Prior to this, the hero taunts Pop quizchemistry 101. What happens when you rapidly cool hot metal? My question is whether this complete immobilization would indeed be the effect of rapidly cooling hot metal. Sorry to bother you with such a question, but Im assuming that it must have a relatively simple answer and that as a professor of metallurgy, you would be the most knowledgable individual at MIT on this subject. Thank you very much, Sam Much to my surprise, I received a response. Date: Thu, 04 Aug 2005 09:21:10 -0400 [09:21:10 EDT] From: Christopher Schuh To: Sam Maurer Subject: Re: Metal cooling question At 05:06 PM 8/2/2005 -0400, you wrote: [Show Quoted Text 16 lines] Hi Sam, Interesting premise you describe here. Rapidly cooling metal will indeed tend to have an immobilizing effect on the atoms, which vibrate more as more thermal energy is available (kT), and less as the temperature is lowered. However, this says nothing about thermal history- if the alloy is at room temperature it is equally frozen whether or not it was heated and quenched to get there. It seems to me that the villain should be frozen prior to the heating cycle in the first place. The other possibility is that the heating and cooling cycle changes the microstructure of the alloy, but the details of microstructure changes are alloy-specific, and probably not the domain of Chemistry 101. As a point of interest, it is worth noting that 4000 K is hot enough to melt every element in the periodic table. Of slightly less technical concern, the comments on the strength of the alloy seem relatively meaningless. While hardness and strength do have different technical meanings, they are actually more or less synonymous. A material stronger than diamond is guaranteed to be harder than titanium and every other material known to mankind today ;) Chris By the time I got this response, I had already e-mailed a similar question to Brian 05, currently a PhD candidate in the department of materials science and engineering. Brian was nice enough to offer some insight into the process at the molecular level, which Professor Schuh found to be beyond the scope of Chemistry 101. Date: Tue, 2 Aug 2005 17:01:45 -0400 [08/02/05 17:01:45 EDT] From: Brian N. To: Sam Maurer Subject: Re: bad science question On Tue, Aug 02, 2005 at 04:44:29PM -0400, Sam Maurer wrote: [Show Quoted Text 20 lines] Oh, this is actually quite accurate. If you very rapidly cool a metal melt, it forms a metallic glass. Of course, all of the organometallic alloys I know of are stronger than titanium, harder than diamond, and dont melt at supernova temperatures, so I guess this doesnt apply this seems to be supported by how they just dont let him melt. I suppose in the case where hes not melted by the supernova temperatures, the structure would already be crystalline and so it wouldnt form a metallic glass. They might be referring to fracturing that could be caused by the rapid shrinking of the metal as local areas experience vast temperature gradients. Of course, that wouldnt solidify him so thats out. Oh, maybe the organic part of the alloy is super strong and prevents him from melting by holding the metal in, even though the metal is actually in liquid form. That would be cool. In that case, I guess the liquid metal part of his system would become metallic glass. Metallic glass is way stronger than crystalline metal (its nearly impossible to break because there arent any fracture planes), so if he was deforming the alloy with the organic part of the matrix, perhaps the organic part was no longer able to apply enough strain to get the metallic part to deform? Yeah, thats got to be it. So have faith in your movie heros, theres usually some way that it might maybe be theoretically possible that what theyre doing would work Oh, the stress fracturing thing I think it basically works like this. High temperature, the spacing between atoms is larger. Low temperature the spacing is smaller. If theres a change of a million degrees over a millimeter of metal (local temperature gradients) thats a really big lattice mismatch between adjacent planes that can cause huge numbers of dislocations to form of course, if his alloy was that strong this would probably just make it stronger, but if it was enough, it might make it crack. I dont think Ive actually ever seen this happen myself though. Brian The secret to living a good life is to find something you truly love to do, and *then* find someone to pay you for it. -Gerry Sussman Well, now you know.