mabuse_
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Cheap Aluminium for Ammonal and Thermite Experiments
Hi,
if you've got the choice between 45µm atomised and 45µm flake covered with stearine - wich one whould you take?
I've already got atomised stuff here. It's incredibly unreactive. How does stearine covered flake compare?
I expect the fat cover to be easier to break through than the oxide layer of the atomised stuff...?
For ammonal tests I'll drop in some percent of Pyro stuff.
Price will be the same.
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Blasty
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Quote: Originally posted by mabuse_  | Hi,
if you've got the choice between 45µm atomised and 45µm flake covered with stearine - wich one whould you take?
I've already got atomised stuff here. It's incredibly unreactive. How does stearine covered flake compare?
I expect the fat cover to be easier to break through than the oxide layer of the atomised stuff...?
For ammonal tests I'll drop in some percent of Pyro stuff.
Price will be the same. |
Define "cheap" in your particular case. How much are you getting such aluminum powders for?
For the same particle size, the flake aluminum is more reactive. However, a very fine atomized aluminum, such as the one sold by Alpha Chemicals
http://www.alphachemicals.com/aluminum_powder
will seem unreactive at first, but once it gets ignited it will react fast due to the very small particle size (at least this is the case in flash
powder experiments.)
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Bismuth
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The stearine coat on the flake water proofs it, negating the reaction with water. It's true that the flake aluminium is more reactive than the
atomized aluminium. But, might I mention that flake aluminium is messy stuff. A lot of people dislike using it just for this reason alone. You'll get
it everywhere and it's nowhere as neat as the atomized aluminium. I've never had a problem with atomized aluminium for thermite experiments (needs
some heat to get it going, but it works just fine). I can't comment on use for Ammonal.
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mabuse_
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| Quote: |
How much are you getting such aluminum powders for? |
10€/Kg
Ok, flake IS more reactive. I don't doubt that.
But how does the stearine coat affect reactivity?
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Bert
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Rinse the stearine off with a couple of solvent washes and test the difference. Unless you're using flash powder in small charges, the stearine won't
matter much in my experience. You should also consider the loading density possible with the two.
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The WiZard is In
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| Quote: Originally posted by mabuse_ | Hi,
if you've got the choice between 45µm atomised and 45µm flake covered with stearine - wich one whould you take?
I've already got atomised stuff here. It's incredibly unreactive. How does stearine covered flake compare?
I expect the fat cover to be easier to break through than the oxide layer of the atomised stuff...?
For ammonal tests I'll drop in some percent of Pyro stuff.
Price will be the same. |
Reactivity is NOT a problem. Remember the melting point of
aluminium is a lot lower than the temperature of the molten
iron produced. I find fine particle Al and either of the three
oxides of iron burn toooo quickly.
I think it was on the Discovery Channel (I am in a rush and
do not have time to check.) The episode where they are building
the new St. Louis Cardinals stadium. They use thermit(e)
to weld RR track, it was well documented.
I do being in possession of a paper on the use of nano materials
in an improved Mil. thermit(e) grenade. Now before all the
WTC Conspiratorial Theory Nuts get in a swivet, the increase
in performance was almost entirely the result of its new mechanical design.
When I have nothing better to do I may scan it.
[Edited on 15-1-2011 by The WiZard is In]
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mabuse_
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| Quote: |
I find fine particle Al and either of the three oxides of iron burn toooo quickly. |
Yes, WHEN it finally burns, the iron gets splattered everywhere, that's my experience too.
I'll try the bright flake. Thanks for your answers.
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iamsmart00
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I use aluminum foil that I grind in a blender for a few minutes on the highest setting and it works perfectly fine for me, plus it is much cheaper
than buying powerized aluminum or aluminum flake from chemical suppliers. Might be worth a try for your experiments
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Fusionfire
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| Quote: Originally posted by iamsmart00 | I use aluminum foil that I grind in a blender for a few minutes on the highest setting and it works perfectly fine for me, plus it is much cheaper
than buying powerized aluminum or aluminum flake from chemical suppliers. Might be worth a try for your experiments
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I hope you don't then use the blender for food, or oxidising agents!
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hissingnoise
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Must be a hell of a blender if it produces fine Al from foil . . .
I have to ball-mill the stuff with lead media!
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mabuse_
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I did that once.
Yes, it works indeed, but it's nowhere cheaper than buying aluminium powder.
You will get little balls of shreded foil, very good for thermite.
| Quote: |
I hope you don't then use the blender for food, or oxidising agents! |
As the aluminium does not get dust fine that should be no problem in this case, it wont get into the motor unit.
And the cup with the knives can be washed.
I wont consider it, its simply not cost effective.
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simply RED
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In my experience with ammonal it does not matter if you use spherical or flake Al powder as far as the booster is 100-200g TNT equivalent. Also my
experience tells adding MNT, DNT, terpentine etc to the ammonal makes far better explosive.
For rocket fuel spherical Al is a must.
When logic and proportion have fallen sloppy dead...
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mabuse_
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| Quote: |
as far as the booster is 100-200g TNT equivalent |
Hey, I'm not a terrorist. That's out of my league
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hissingnoise
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| Quote: | ]I did that once.
Yes, it works indeed, but it's nowhere cheaper than buying aluminium powder.
You will get little balls of shreded foil, very good for thermite. |
If you mill cigarette foil you'll get a very fine powder - the backing paper will form tiny globules that won't affect the Al.
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simply RED
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The intimate nature or ammonium nitrate energetic materials require the use of proper booster. Anything less than 40 grams tetryl is totally
impractical.
100 grams TNT eq is just about 70g AN + 50 g PGDN. It is not that much...
[Edited on 13-7-2011 by simply RED]
When logic and proportion have fallen sloppy dead...
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