Will copper foil withstand a wood fire?

It's right on the edge, Alan. From my reading, a campfire can get up to 2000*F, and copper melts at 1984*F. Maybe if you kept the copper off the coals it might be a bit cooler? If you try it, please post your findings.

No.

I tried using copper pipes in some high temp applications after checking its melting point. I never got near the melting point, but got a lot of oxidization. Something as thin as foil would go very quickly. More so in a camp fire if it ever contacted the flame - flames have far more reactive species than molecular oxygen in them.

If you are using the foil on a water pot that can act as a heat sink - maybe. The shorter the fins and the better connected they are to the pot, the longer lasting they will be.

I was experimenting with a lot of materials for making a little backpacking wood stoves about six months ago, and I decided to test them by putting them into the coals in my big kitchen woodstove at home. I wanted to see which of them would withstand the heat of a wood fire.

I had little credit-card sized pieces of various foils (copper, brass, 304 stainless, 309 stainless, 316 stainless, CP4 titanium, CP2 titanium, 6Al 4V titanium, 15-3-3-3 titanium, molybdenum, inconel 718, and inconel 600) in various thicknesses. I also has short lengths of wire/rod in many of the same metals, and I had a collection of glass and ceramic fiber woven fabrics (E glass, S2/Zentron glass, basalt fiber, vitreous silica fiber, quartz crystalline silica fiber, silica/alumina fiber, pure alumina fiber, and zirconia fiber).

Almost everything melted or burned. The heavy inconel wires and the zirconia cloth were the only samples that survived basically unchanged except for discoloration. The alumina fiber cloth survived but became very brittle. All of the titanium turned to ash. The molybdenum and the finer steel wires burned away completely. The heavier steel wires, the steel foils, and the copper and brass melted into little puddles. The glass and basalt fabrics melted, and the silica fabrics turned to dust in my hands when I tried to fish them out the next day.

So, woodfire temperatures vary over an enormous range. Even titanium and steel melt or burn in a very hot wood fire. But in the relatively cool fire in a backpacking wood stove, copper should be fine if it is kept away from the hottest parts of the fire. It might oxidize a bit. If it is a larger stove and you plan to load it heavily and use it for long burns, it might not do so well.

Edited by ckrusor on 05/01/2012 20:01:33 MDT.

Remember, copper was the first metal man started to smelt consistently. Mostly because it was pretty easy to do so in a standard fire fed by strong wind.

With copper foil being so thin, I wouldn't trust it for any long term use. Between oxidation and simple melting you'll burn holes through it pretty quick.

Of course it also depends on what you're using it for. More details and we may be able to give you better insights.

I would note that copper will loose temper very quickly, too. It will get very soft at temps far below the actual melting point. As a pot, yeah, it will work. For a stove, no. It gets too soft to handle. Foil is just too thin. Brass shim stock would be a better choice, but even this can get soft when heated to 450-500F (soldering temp.)

FWIW, copper is also significantly heavier (as in denser) than steel. Not sure what the advantage would be (at least in pot or windscreen application), even if it did withstand wood fire temps.

Edited by DavidDrake on 05/02/2012 09:45:01 MDT.

Alan, how do you plan to use it?

To be Used as non-weight bearing windscreen in a wood stove to seal holes in cutlery holder.