Making a Microporous Aluminum Grid

I recently bought a Scripto Windresistant igniter, which is a butane powered gadget for starting barbeques and the like. Sort of like a big disposable
cigarette lighter, but with a long wand between the fuel supply and the burner, and a piezoelectric starter. Only $6.
I was impressed by the cone of flame, which had a bright blue cone inside a purple flame, like a Bunsen burner. I thought it would be interesting to see how much damage it could do to aluminum foil. I only had the thick "heavy duty" foil, from which I tore a strip. I folded it into an L-shaped channel, which I stood up on one leg, so I had a vertical target.
I could heat it up to orange heat in a couple seconds. I thought I should be able to burn through it in just a few seconds more, but even at 30 seconds I wasn't making any more progress.
The spot I had been attacking was obviously disturbed, but not punctured. Then I noticed there was light coming through. I held it up to the light, and I could see it had turned into an array of very closely spaced tiny holes. I wished I still had my Radio Shack Pocket Microscope, so I could see how regular they were.
I was amazed that the foil had formed this array, rather than just melting and/or burning. Once formed, the array was very resistant to further change. The phenomenon is very reproducible. Every time I tried it, it worked just fine.
Hmmm... there must be something clever I can do with this discovery. I wonder if it has a name?
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|> I recently bought a Scripto Windresistant igniter, |> which is a butane powered gadget for starting |> barbeques and the like. Sort of like a big disposable |> cigarette lighter, but with a long wand between |> the fuel supply and the burner, and a piezoelectric |> starter. Only $6. |> |> I was impressed by the cone of flame, which had |> a bright blue cone inside a purple flame, like a |> Bunsen burner. I thought it would be interesting |> to see how much damage it could do to aluminum |> foil. I only had the thick "heavy duty" foil, from which |> I tore a strip. I folded it into an L-shaped channel, |> which I stood up on one leg, so I had a vertical target. |> |> I could heat it up to orange heat in a couple seconds. |> I thought I should be able to burn through it in just a |> few seconds more, but even at 30 seconds I wasn't |> making any more progress. |> |> The spot I had been attacking was obviously disturbed, |> but not punctured. Then I noticed there was light |> coming through. I held it up to the light, and I could |> see it had turned into an array of very closely spaced |> tiny holes. I wished I still had my Radio Shack Pocket |> Microscope, so I could see how regular they were. |> |> I was amazed that the foil had formed this array, |> rather than just melting and/or burning. Once formed, |> the array was very resistant to further change. |> The phenomenon is very reproducible. Every time |> I tried it, it worked just fine. |> |> Hmmm... there must be something clever I can do |> with this discovery. I wonder if it has a name?
It sounds like you oxidized it into alumina before it could melt leaving a refractory material with voids where outgassing occurred. Try it with several layers pressed together and cover up the air holes a little to get a carburizing flame. If it inner layers melt away you know you were making alumina. Should be worth a Faces in Science mention in USA Today followed by a Leno and maybe an SNL walk-on, then the book tour and finally your own Fox series. :-)
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