A strange lump of metal... -- myArmoury.com

Gabriele A. Pini · Posted: Mon 09 Mar, 2009 1:34 pm Post subject: A strange lump of metal...

Two weeks ago a sword of my company was broken in half during a fight: it wasn't a good sword, not for a long shot, and I seized the opportunity to eliminate something that was very embarassing to me, with its word "excalibur" on the pommel and the simil-celtic dragons on the hilt (I know, it was horrible, but for internal politics I couldn't remove it sooner), and I transformed it in a long knife, grounding the hilt and the pommel.

The second half, shorter, I thought to transform in a simple knife for me, with a wood grip and no pommell or hilt. I'm not an expert, but with the long work I did to the other half I judged it of cast-iron, and thinked of toughen it in a fire (of beech-coal) and in the meantime remove some carbon from it by placing it near the fan...

I have see some very strange things in my short life, but this is the first I see a lump of metal burn to nothing like paper, with a very pretty green-blue flame and not a residue to speak of (I know, I have searched and cleaned the whole fireplace).

Any ideas about this story? What metal cuold it have been? The only one I know that burn like that is the U238...

Joel Minturn · Posted: Mon 09 Mar, 2009 2:20 pm Post subject:

Sounds like it was made of Aluminum. The temp range for melting aluminum and having it burn up is rather small. That's why when you put an empty aluminum can in a fire it disappears instead of having a pool of molten aluminum at the bottom of the fire.
Thats my guess.

Jared Smith · Posted: Mon 09 Mar, 2009 2:42 pm Post subject:

Fairly pure aluminum should burn with more of a silver color. If the color you saw in the flames was "blue" and "green" it sounds like it was an alloy that included some copper and barium compounds, probably some residual chloride/salts.

If your coal fire pot was hot enough, you could have completely burned up a wide range of steel alloys. That was my first mistake in improper blower / fire management a couple of weeks ago. I got a steel rebar got hot enough to spark (like a fireworks sparkler) on a couple of heats. Then on another excessively hot heat, it completely "disappeared" !

Joel Minturn · Posted: Mon 09 Mar, 2009 3:04 pm Post subject:

There are many different types of Aluminum-Copper alloys which could account for the greenish flame. But one question.
Did the metal turn red and start to glow before it burned or did it just catch fire before it had a chance to turn colors?

Aluminum and the various Al alloys have an annoying habit of starting to melt and burn before they turn red unlike steel.

Gabriele A. Pini · Posted: Mon 09 Mar, 2009 3:17 pm Post subject:

The metal melt, and when I grasped a small piece and passed over a burning coal it catched fire with the aformentioned blue-green flame.

I don't really know what the other half-span did, because I wasn't here to see it. I have ten cm more of it, and I can experimented with it if you need some inputs (but not with the beech: here in Como is too hot to light the fireplace at the moment),

Tnks for the posting and good night!

Joel Minturn · Posted: Mon 09 Mar, 2009 9:03 pm Post subject:

A simple test to do, if you have a good magnet take it to the metal. If it sticks then it is steel. If it doesn't, well that doesn't leave too much out. Then, if you wanted to, you could try heating it up again. If it starts to glow red and brighter then it is steel. If the metal stays metalic and shiney but starts to melt and burn before changing color than it is most likely some alloy of aluminum. Look for pictures of forging metal if not sure what a red hot piece of metal looks like but I'm sure you do.

Bruno Giordan · Posted: Tue 10 Mar, 2009 1:25 am Post subject:

Exactly what happened to me two years ago with another broken SLO that was originally one of the cheap eastern european mass produced blade italian reenactment groups like so much.

It wrapped up almost like tinfoil.

Such blades have a strange alpaca like color, a sort of silver-ish or goldi-ish dominant, quite slight but perceptible.

They look quite fake to an expert eye. The only usable technique for such ***ish stuff is grinding them to a new shape, I guess.

JE Sarge · Industry Professional

Alot of SLOs, especially those made by Denix, are made from a zinc alloy. I guesstimate without seeing it that this was made of the same type alloy. I once had a gladius replica made of this stuff that melted almost like candlewax when exposed to a propane torch. WTF?!