Sciencemadness Discussion Board

How to make Aluminum foam

symboom - 13-5-2018 at 12:06

So i read that magnesium carbonate or calcium carbonate can be used to make aluminum foam because they act as blowing agents tge molten aluminum is pored onto nagnesium carbonate and tge magnesium carbonate decomposes forming magnesium oxide and aluminum foam and carbon dioxide

VSEPR_VOID - 13-5-2018 at 14:02

Do you have a link to a source? What keeps all the carbon dioxide from bubbling to the surface and escaping?

symboom - 13-5-2018 at 14:06

I think it keeps it from escaping is a pressure device so the co2 is forced into the aluminum i seen a video on how they make that foam

I would think that dry ice co2 would do the same although that would also be dangerous

I would have to be some sort of glass microsphere

Or something solid that can be disolved out

https://www.google.com/url?sa=t&source=web&rct=j&...

[Edited on 13-5-2018 by symboom]

Foeskes - 13-5-2018 at 15:41

I wonder what's the solubility of co2 in aluminium. Apparently Aluminium foam is prepared by dissolving a lot of gasses in Aluminium and allowing it to come out of solution whist cooling.
Of just constantly bubbling it.

MrHomeScientist - 14-5-2018 at 05:45

Low, I would think. Metal casters use CO2 to degas aluminum before casting, to eliminate voids in the final metal piece. Hydrogen is highly soluble in molten Al, so that should be better for foam making.

[Edited on 5-14-2018 by MrHomeScientist]

Σldritch - 14-5-2018 at 11:33

Quote: Originally posted by Foeskes  
I wonder what's the solubility of co2 in aluminium. Apparently Aluminium foam is prepared by dissolving a lot of gasses in Aluminium and allowing it to come out of solution whist cooling.
Of just constantly bubbling it.


Would'nt it just react with the Aluminium to form Carbon Monoxide? It may form Carbon too but that is not favored by Le Chatlier's principle.

As for the hydrogen, should it not be more soluble in Aluminium at lower temperatures? Unless you change the pressure i do not think it would work very well as a foaming agent but at that point it starts to get very hard for the amateur. I think gas generator or dissolvable filler is the way to go.

Bert - 14-5-2018 at 14:23

Titanium hydride as a blowing agent?

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