So me and a friend were chatting online about thermite.

I don't mean just any thermite. Apparently he has a bucket of rust lying in
wait. A *five gallon* bucket. The kind of weighty bucket that your health
insurance shudders to see you lifting with anything but your legs.

We were talking about pouring something nice and weighty, like a small
anvil. Which, ironically, is a rather *large* thermite pour.

That's only half (well, three quarters) the problem, but assuming the
requisite 25% aluminum can be found in a suitable form (powder, filings,
swarf, maybe even bulk?), that just leaves the question of the metal. Well
I know from experience that thermite metal sucks. It always seems to be
brittle, I would guess from sulfur. A desulfurizing agent would be handy.
Then assuming the rust itself is pure iron oxide, that leaves carbon and
whatever the hell else it needs to make a happy chunk of metal.

Now this is where it gets creative... we were thinking, to start, roast the
rust up to about red heat, in open air, to drive off as much sulfur as
possible. Then, at the bottom of the ignition crucible, a dash of
magnesium, or since that'll make a horrible mess of flying molten iron,
something saner like calcium silicide maybe. Any idea where to get that?
It'll add silicon too, though that isn't a concern since I already have a
few pounds of 75% ferrosilicon.
Then there's carbon. Carbon doesn't dissolve quickly, AFAIK. I've heard of
successful iron melts in *SiC* crucibles. Can't be too happy for the
crucible, but apparently the iron goes through the ordeal indifferent. I
could run the molten steel through a pack of coarse charcoal, but that
doesn't guarantee *anything* about how much is going in and how much
charcoal stays behind!
Some manganese would be nice, but I have some MnO2 on hand that can be
folded into the thermite charge to cover that dash of salt. To get an
actually useful anvil, some other metals would be welcome additions, maybe
some chromium, vanadium or molybdenum? From what? (I'm working on
seperating chromium metal from stainless, but until that's done, I have some
green Cr2O3 that can also be added to the charge.)

Then 'cuz thermite is half slag, half metal, I thought a skimmer gate would
be a good idea. But then, add some limestone gravel to it, think loose
ceramic foam filter. The lime will be fired to remove that ever-so-evil
sulfur, which will also make the lime soft and weak, but it should hold up,
assuming it doesn't get swept into the mold anyways!
Then because the charge will yield metal at about 4000°F, I was thinking,
for the skimmer gate, have it open to air so it can radiate a bit before
sloshing into the mold. And put ground charcoal, or ferrosilicon, or
something in and/or on the mold to keep it from oxidizing too badly in the
process.

That's my story and I'm sticking to it, oh wait, no I'm not, I'm looking for
comments!

Tim

P.S. Yes, video will be in supply if it comes to fruition!

--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms