Problems With Mgal Making

[Pyrostar]

Hi

I started making MgAl the first time today and I was very disappointed.

I took a camping stove, a metal pot and aluminium and magnesium to form the alloy.

I turned on the camping stove, put the metal pot on it and
covered the pot with a lid.
Then I waited till the pot was red glowing, and dumped
balls of aluminium foil in it and waited for 10 minutes to melt it.

The pot was glowing bright red all the time, but the aluminium foil only got a
weird colour, but it didnt melt, although the temperature must have been higher then 700°C.
Then I to added magnesium, and that melted quite well, resulting in a bright fire.

I ask myself why the aluminium didn´t melt, I am totally new to metal-alloying and I need a few
tips how to get it right

Which sort of gas burner should I buy, or do I need to take massive aluminium instead of aluminiumfoil balls?

Pyrostar

The anode where I got my Mg from:

Edited April 26, 2008 by Pyrostar

[Keesthemad]

As you might know, aluminium is very good at conducting heat. The foil you use makes your ball covered with small membranes, cooling fins if you wish. Start with some solid aluminium, and work with a good lid, then you won't have fires anymore.

Kees.

[Pyrostar]

Hi

Today I realized that my campingstove adapter cracked ( it looks like
a bell and has a lot of holes, resulting in a flatter, and wider flame),
I dont know the proper name for it.

Anyway, I discarded it, and now I have a little pipe screwed on the gas-valve,
with little vent holes.
The stove is fueled with a 190g butane-cartridge.

Can I attach a pipe to the stove to make a smaller, but very hot flame, similar to a bunsen burner?
The main reason of my thought is that I go to the craft store tomorrow and buy some fireclay to
make a furnace for meltng MgAl.
I want to use the burner for the furnace if I can make it hotter burning

This is the stove without the adapter and the pipe attached: ( the black notch is the gas-valve)



So to cut the story short, I want to put the pipe on the burner, and take a steel pipe to make it
longer, So I can fit into the furnace.
I want to have a nice jet flame, but I dont how long the pipe should, as well as how much
holes I should drill in the pipe.


Pyrostar

Edited April 27, 2008 by Pyrostar

[miech]

Maybe you could better use (char)coal to produce the heat for melting your metal. By blowing a constant stream of air through your coal you should be able to reach 1500 centigrades.

[Blaf]

Hello guys

I see this has gone far enough...there's a perfect place where you could find everything concerning propane burners and melting techniques. Hope this link helps: http://www.backyardmetalcasting.com/oliverburner1.html

Blaf

[Pyrostar]

Hello all

I have made my first MgAl today, and I am very satisfied with the result.
I used the blower I made, and when the coals were glowing, I added the blower
put the crucible in the fire, add the aluminium and put a brick over the crucible.
The aluminium melted in 10 minuts after I turned the blower on.
Then I added the magnesium wearing leather gloves, gummi boots and safety glasses.
This is a MUST!
After 15 minutes the crucible was opened again to stir the melt.
Because the MgAl ignited only a little I kept on stirring.
Then the crucible was taken out of the fire to let it cool.
While it cooled some very strange noises could be heared, I only needed a whack with the hammer
to get the MgAl chunk out of the crucible.
It is pretty amazing how brittle this alloy is.

This is the blower:



A larger batch has to be made, since the process is so fun and easy and I got awesome results.

Thanks for all your advices, they helped me very much!

Pyrostar

Edited April 30, 2008 by Pyrostar

[icarus]

when the magnesium is added you can remove crucible from heat, stir slowly with steel rod to mix then drip magnalium slowly into water ,It makes strange noises and forms pieces full of gas bubbles but it is then very easy to grind it up

[Tyneman]

I made my first MgAl yesterday. Made it in a 'moffeloven' have no idea what it's called in english. All @ 850 Deg. C.
Pics of the process I will post later. Here are the results.
A 40g MgAl 50/50 ingot. Broken in half, one half crushed up with a few whacks of a hammer.
http://pyroforum.nl/uploads/post-149-1216109528.jpghttp://pyroforum.nl/uploads/post-149-1216109511.jpghttp://pyroforum.nl/uploads/post-149-1216109494.jpg

[Yawznug]

Looks very good.
I need to make some MgAl soon due to the fact I want Crackling Micro Stars.
Would aluminum cans be "pure" enough as the source of aluminum

[lootens]

I think not alu cans are moisent but you can pure the alu from cans.

[miech]

Aluminium cans are coated with some kind of plastic, so you'll have to burn it off before melting. Also, the lid is usually not made of aluminium, so cut it of and discart it.

[Leander]

Aluminum cans are way to thin to be molten. Their surface area is a lot larger than an ordinary block of metal. They are more likely to burn than to melt IMO. Finding thicker aluminum is IMO not such a big deal, moreso since the process of making MgAl (without shitloads of Al2O3 that is ) is quite time consuming project. Melting it in an oxygen poor/free environment would work. One of the best methods to do so is by wrapping it in steel foil. This can be found in the workshop of a modern blacksmith. It is essentially verry thin steel foil with a really high melting point. A bit of flux is stuffed between the joints of the foil, and there you go, melting aluminum completely oxidefree! Other alternatives are a crucible with a good lid, of preventing oxidation by chemical means, for example by putting a small amount of sulfur on top of your (semi)molten metal. :blush:

Edited July 21, 2008 by Leander

[leosedf]

I think for flux you could use KCl.

Suppose you made some MgAl and you smack it with a hammer. What is the particle shape of MgAl? Flake?

[miech]

I think you'd rather get it in granular shape. To get flakes you need to ball mill it (which I do not recommend) for quite a while, but it gives you smaller particles too.

[leosedf]

Hmmm. True..

I have to get a graphite crucible case the last one melted and it was spilled on the ground. Jewellery worker shops have stuff like that and you can get allmost any size you want. Graphite is ideal for the job.