metal or ceramic foam

The following recent article on (terrestrially-produced) ceramic foam may
be of interest.

http://www.sciencedaily.com/releases/2001/05/010518082028.htm

Ron Menich

Ian Woollard
ssi_list@...
05/20/01 07:55
PM
Please respond
to ssi_list

> Hi,
> Does anybody know anything about how foams are produced and could one be
> made from liquid metal in zero gravity vacuum?

Not a lot, although I just started thinking about it.

I'm sure that this has been done with a molten liquid in zero-g
already- water is a molten liquid isn't it? ;-)

I believe that blowing gas into a liquid (similar to the way you
can blow bubbles with washing detergent on earth) would
work fine... You can adjust the size of the bubbles by controlling
the width of the gas tube(s) and how fast you blow. You can also
move the tubes around to ensure separation of the tubes from the
bubbles at the right time.

> I have been thinking about how to capture and use asteroid material.
> The capability of spewing out a metal foam sheet or I beam a mile long
> could be of greater use than the same amount of material in compressed
> form: fewer viberational modes, greater cross-section, restricted
> localized damage. Each of the bubbles would be pressurized and would
> therefore have more strength then if made from a honeycomb type
> laminate. I would think that metal foams would be very rare on earth
> because gravity would swamp surface tension affects. In zero gravity
> the opposite would be true.

Yes. Good thinking.

> Mitchell James
> mejames@...
> http://www.InnerTransit.org (homebase for collaborative engineering)
> http://www.InnerTransit.net (email distribution for distributed multi
> level organizations)
>

civilization?"