Making atomized aluminum

[NeighborJ]

I am curious if anyone else had tried to make atomized aluminum. About a year ago I did an experiment to see if it can be done at home. I used an angle grinder with a cupped grinding stone, it was placed in a clean 55 gallon drum and fastened to a cinder block. The trigger was locked on and a 1/2" of water was poured into the bottom of the drum. When molten aluminum was poured into the spinning stone it was flung out into spherical balls and promptly quenched by the water. Some problems I encountered was a buildup of aluminum spatter on the walls of the drum but this was reduced when I cooked the molten AL to just above its melting point. Buildup of spatter on the walls became a real issue but as long as I could promptly clean it off with a stick and spray down the outside of the drum with a hose it was manageable.

I had planned to place an argon purge in the drum but didn't find it necessary because it didn't ignite.

I am sharing this because of the recent AL powder ban in EU and I know if I lived there id be looking for some new options. Maybe there are others here who are willing to share other teqniques.

[DavidF]

Heh heh, I don't think the Europeans are too worried about glitter Assuming the atomized aluminum is a starting point for aluminum flake, my choice would be to abrade the aluminum instead of atomizing it, and go from there.

 

Just to see if I could, I took a can of aluminum paint, separated the aluminum, washed it with solvent more than once, and made some very good 70/30. The larger particle size of the paint flake aluminum is a non-issue with larger salutes.

[Nitrotitanite]

It would be very useful indeed a nice guide on pyrotecnico aluminum production.

Now that these substances have entered the list of explosives precursors will be very difficult to obtain and the EU restrictions, the biggest problem will be to find good magnalium fact the list is also specified powders with more components.

[Nitrotitanite]

The dark aluminum (also said pyrotechnic aluminum) is a mixture that contains a percentage of carbon that varies from 12% to 22% (in the form of graphite or coal). The remainder is formed by finely pulverized aluminum, with an average particle diameter of which varies from 2 to 8 micrometers (depending on the type).

The aluminum alloys most commonly used for grinding (after mixing with the coal) are:

3413;

4413;

5413H;

6413.

Compared to the normal aluminum powder, for the presence of carbon as a lubricant, it presents a greater ease of ignition, pyrophoricity anything, greater smoothness, but also a lower combustion temperature.

It is a highly flammable product and is explosive when in contact with combustible substances.

 

Fonte:Wikipedia.

 

In the precursor list is not specified aluminum fireworks but by containing a high concentration of course is among the prohibited components.

[kleberrios]

I am curious if anyone else had tried to make atomized aluminum. About a year ago I did an experiment to see if it can be done at home. I used an angle grinder with a cupped grinding stone, it was placed in a clean 55 gallon drum and fastened to a cinder block. The trigger was locked on and a 1/2" of water was poured into the bottom of the drum. When molten aluminum was poured into the spinning stone it was flung out into spherical balls and promptly quenched by the water. Some problems I encountered was a buildup of aluminum spatter on the walls of the drum but this was reduced when I cooked the molten AL to just above its melting point. Buildup of spatter on the walls became a real issue but as long as I could promptly clean it off with a stick and spray down the outside of the drum with a hose it was manageable.

I had planned to place an argon purge in the drum but didn't find it necessary because it didn't ignite.

I am sharing this because of the recent AL powder ban in EU and I know if I lived there id be looking for some new options. Maybe there are others here who are willing to share other teqniques.

 

Hi. I am working in the same teqniques about 2 years but to produce atomized Mg, and have some ideas.But instead of using cupped grinding stone I used a straight steel disk, with no apparent screws.

 

On the wall of the drum must have a stream of water so the particle does not deform as much, and cools it quickly. I spent years grinding the propeller blades of the Hercules C-130 and Bufalo C-115 (already deactivated) to remove small holes produced by sand. In this room there was a wall of water to collect the dust from Al. In our case the wall has to have 360 degrees around the drum. The disc can not have an apparent nut, so as not to disturb the atomization. The higher the rpm, the finer the Al.

 

Al molten from being poured exactly in the center of the disk, for this you can use a steel funnel with a 3mm hole, because the thinner the thinner aluminum fillet will be the atomized Al.

 

I use this technique in a water atomizer, installed in a fan. Now my next step will be to build my metal atomizer using the same process.

https://www.youtube.com/watch?v=gLZ1q4oPCGg

 

Edited March 4, 2017 by kleberrios

[PyroFrank]

NeighborJ, I'm curious about your setup, do you happen to have any pictures from it? How were you able to position the angle grinder so it was stable on its own? Was it a cordless grinder? Also weren't you afraid that the metal might land on the grinder itself? Did you get usable atomized al from the process? I would like to recreate this if possible since I have a foundry for melting metals

[NeighborJ]

Im sorry Frank, I never took pictures, it was before I joined this forum. I had made about 6-7 pounds while experimenting much of it was -20 mesh but I did get a small amount which I would catagorize as 325 mesh. I think if I would do this again I'd use a wire wheel cup brush to try to force the aluminum into smaller beads and also try kleberrios suggestion of a mist of water running down the walls of the drum.

To answer a few questions, I slid a piece of pvc over the power cord to protect it from spatter, the grinder was tied to a cinder block with bailing wire and a small scrap of fire blanket was placed over the body to protect it. The whole shebang was dropped into the bottom of the drum to catch the aluminum and didn't fit centered but it made no difference. I plugged in the power cord remotely and poured approximately 1/2 cup of molten AL at a time. It seemed to work best when it poured slowly.

I'm sure that you use a leather jacket and face shield when working with metals but I just want others reading this to be aware that protection is a must. Those beads and steam go everywhere, if you aren't protected you WILL get burnt or blinded.

I still have and use the aluminum but it is too coarse for glitters and the metal streamer stars leave a tail which falls for 300' before burning out. I could screen out the small stuff but it's been more convenient to use the pre-screened and commercially available stuff. To be honest I keep forgetting I have it.

[PyroFrank]

Thanks for the info, maybe I'll give it a shot when I have some time. Will probably try using a wire wheel too. Seems a bit sketchy, but the idea of being able to reduce the aluminum down to such a fine particle size so quickly is also quite tempting. And you're right, if I do this my PPE better be on A-game. I've got a face shield and apron which would hopefully be enough. I mostly want the al for star comps, but if I end up with a lot of the coarser stuff like you did, I suspect it wouldn't be a bad starting place for milling down to finer sizes.