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Discussion in 'General Chatter' started by harolds, May 4, 2017.

  1. harolds

    harolds Member

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    Over the years of reading WW2 books, I often run into descriptions of explosives used in torpedoes, shells, mines, etc. Often, these explosives are laced with aluminum powder. It seems that aluminum powder increases the yield of the explosive but I've never understood why. Would someone here please explain how aluminum increases the power of TNT and other explosives?
     
  2. OpanaPointer

    OpanaPointer I Point at Opana Patron   WW2|ORG Editor

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    Look up thermite.
     
  3. lwd

    lwd Ace

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    It readily combines with oxygen and quite exothermally. Given a bit of heat the reaction is also quite rapid but it's fairly stable otherwise.
     
  4. wm.

    wm. Active Member

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    It depends on what else was in the explosive.
    It reacts violently with ammonium nitrate, no TNT is needed. One example is the well known to some Americans Tenerite.

    In a mixture of TNT and aluminium, aluminium doesn't react, violently or not, with TNT or any products of its detonation.
    The detonation dispers aluminium and the heat ignites it creating a secondary explosion. In effect we have a crude thermobaric weapon. In this case aluminium uses atmospheric oxygen, so the main benefit is the explosive doesn't have to carry oxygen for it.

    Thermite is something else, in thermite aluminium "steals" oxygen from another metal (properly its oxide) releasing energy.
     
  5. OpanaPointer

    OpanaPointer I Point at Opana Patron   WW2|ORG Editor

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    Yer gettin' too bloody technical, mate. ;)
     
  6. harolds

    harolds Member

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    Ah so! Thank you wm.! So what they got was a double explosion but so close together they were essentially the same explosion.
     
  7. wm.

    wm. Active Member

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    Something like that. I suppose they didn't care much about a double explosion or even about creating a crude thermobaric weapon. The intention was to replace some of the weaker explosive (TNT) with a stronger and maybe cheaper one (aluminium).
    But aluminium is very hard to detonate, it has to be subjected all simultaneously to a very high temperature, so only small amount of TNT could be replaced with aluminium.
    Aluminium itself doesn't want to explode, at best it burns slowly.
     
    Last edited: May 6, 2017

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