Amorphous metals are not particularly new, nor were they developed for defense purposes. Their principal use is in the special magnetic steel used in the cores of electric power transformers. Magnetic domains are crystals, so the elimination of crystals changes the magnetic properties of the steel such that it doesn't heat up as much as its magnetic field is repeatedly reversed. While amorphous metals are undoubtedly used in other applications, I rather doubt that amorphous copper would be of great benefit in audio work. I would also want to investigate whether the crystals re-form in the wire-drawing process, which severely deforms the wire and thus necessitates annealing between successive dies.
