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Creating plasma using thermite?

  1. Dec 27, 2011 #1
    Could thermite be used to bring certain types of matter to a plasma state? If so what materials would be easiest to render into a plasma? Inspired by the german experimental shockwave cannon from WWII...

    I got to wondering. If a 3 layered charge were used in such a weapon, one layer a finely powdered & compressed thermite mixture is both ignited and propeled by an explosive charge layer, could that ignited thermite layer render the 3rd layer [also a finely powdered & compressed element] into a plasma state in travel. Such would create a weapon that fired a torroidal shockwave of super hot plasma. Thus creating the worlds first true plasma cannon.

    The shockwave cannon already exists. [though the barrel would probably have to be lined with tungsten]
    Thermite is a well known substance.
    2 out of 3 pieces of the puzzle are already there. All that remains is identifying a element that a thermite reaction can be ionize and render to plasma state in the time it takes the shockwave to reach the end if the barrel, or very shortly thereafter.

    So. Does such a 3rd element exist? Is it possible?
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Dec 28, 2011 #2


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    Staff: Mentor

    Chemical reactions won't be able to heat the gas up to required temperatures. Even substances of the highest chemical energy density won't heat up products of their reaction past several thousands Kelvins (say 4000K) - rather low for a plasma with an air density.
  4. Dec 28, 2011 #3
    What about elements with very low melting points and high ionization potential like cesium? The charge propellent would very likely be a small amount of high explosive. High explosives are typically detonated with a small electric charge are they not? Simply ramp up the charge by an order of magnitude to accomplish both the detonation and assist in the ionization of the target element.
  5. Dec 28, 2011 #4


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    I don't see the point. Shooting a plasma into the air is a terrible idea for a weapon. It simply dissipates and cools down very very quickly.
    Not to mention the fact that as Borek said, chemical processes don't make very good plasmas.
    Last edited: Dec 28, 2011
  6. Dec 29, 2011 #5
    Actually, torroidal shockwaves do not dissipate easily like other forms of shockwave & could very easily be used to carry a charge of particulate matter. Some material may be lost in transite from weapon to target due to heat expansion but since the charge would carry not only the chemical plasma but also the ingited thermite particulates I would expect it to retain sufficient heat for several hundred yards. Considering that most violent engagements take place within 300 yards, the weapons viability is retained. Even is plasma was discounted as viable a weapon that could fire an ignited shockwave of burning thermite particulate would make a very effective weapon. Sort of like a long range flame thrower with the impact of a close range shotgun blast.
  7. Dec 29, 2011 #6

    These are several example of torroidal vortices. Note that even though many of them spin outwards rather than inwards like the intended weaponized shockwave they still manage to travel considerable distance relative to the force behind them.
    Last edited by a moderator: Sep 25, 2014
  8. Jan 15, 2012 #7
    I dont have much to add but imho Id say a better/cooler ideato look into would be an electrolaser, use a very intense to ionize air and then send current down it to the intended target. Range would probably be a good deal more than sending out a toroid and could be quite accurate over distance. Energy consumption would most likely be more than it would be worth though...
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