nezza
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Magnesium flash powder isnt
Hi
I have recently tried to make small amounts of magnesium flash powder using some magnesium powder bought over the internet and various oxidisers,
potassium nitrate, permanganate and even chlorate in various ratios. All I ever get is a fizzle. I succeeded many years ago with magnesium and
potassium permanganate, but cannot repeat the experiment. I am assuming the magnesium is at fault, possibly contaminated with oxide or nitride. If so
how do I test for purity ?.
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Bot0nist
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What ratios of fuel to oxidizer did you use? What was the partial size? My experience with Mg flash has always been impressive.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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woelen
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Just take some magnesium without anything mixed in. Put it on a metal spatula and keep in the flame of a candle. It should ignite immediately and burn
with a fierce white flame. Even fairly coarse Mg powder of 100 um or so is very easily ignited and fiercely burns. If your powder does not, then it
either is very coarse (200+ um) or it is heavily oxidized.
Another thing could be that you have magnalium. Magnalium is not that easily ignited, but when mixed with KClO3 it should give a decent flash.
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quicksilver
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On the opposite end of the discussion, search on extremely small particulate Mg and ignition. There had been some discussion on this topic some time
in the past. Single micron (2-9 um) particulate Mg can condense & as it is granular (doesn't appear to flake) form a difficult to burn product
similar to a solid in some instances. While oxidation may be problematic it's generally got to be pretty significant - at least you should be able to
see something at 100-400x magnification.
Flare production with Mg is rather tricky and the particulate is often suspended in a binder prior to mixing due to this tendency to "clump" together.
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nezza
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Thanks for the info. As regards Oxidiser/fuel ratios I have tried
(Oxidiser/fuel) 2:1, 3:2, 1:1, 1:2
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quicksilver
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Push it to 3:1 (oxidizer/fuel ratio) & test and VERY small sample (like a match-head size of 10mg). If you're not getting anything (IMO) you may
have Mg/Al or the material is SO heavily oxidized that you may need to deal with that before anything else. Even w/ Mg Al you should get something at
that ratio. Make very sure the mix is well completed and the oxidizer is not moist or in some manner compromised, etc.
Do you have any picture on a macro level showing size comparison ( to, perhaps, the head of a pin) of the fuel?
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