I wondered if magnets could be used to hold a drop of molten liquid metal in air (not for any particular reason just because it could be done), but was disappointed when a quick Google search showed the metal would lose its magnetic traits before it melted.
Are there any other forces that could be used to suspend a drop of molten liquid metal in air such as sound waves, high pressure air, electric currents, or anything else?
Yes, it is possible to magnetically levitate molten metal. This is not due to ferromagnetism however. As seen in the below references, the metal sample is placed within a tapered conducting coil, which carries alternating electric current in the ~400kilohertz range. This sets up a magnetic field gradient inside the coil and causes eddy currents in the sample. The applied magnetic field is excluded from the interior of the sample. The sample experiences a force in the direction of decreasing magnetic field strength.
See the following for more information:
http://www.youtube.com/watch?v=intDuSJ2_PA
http://www.youtube.com/watch?v=Q6Zrnv4OtbU
http://www.google.com/patents/US2686864
http://www.google.com/patents/US2686865
http://www.cs.duke.edu/~reif/temp/MagneticLevitation/LevitationSuveys/Levitation%20in%20Physics.pdf
Molten glass is suspended (and spun) on air jets to form "pre-forms" for molding glass optics. I suspect that the same must be possible for metals.
