The ability of electrons and phonons in solids to equilibrate is fundamental to the thermodynamic and
transport properties of these systems. Nonetheless in mesoscopic systems sufficiently high current densities
can lead to situations where the phonon subsystem can no longer reach a steady state. In previous work
this phenomenon was connected with the demonstration that interatomic forces under current are non-
conservative, with the ability to do net work around closed paths in the nuclear subspace. Here we consider
these effects in bulk systems. We arrive at a critical current density beyond which current flow results in the
uncompensated stimulated emission of a blast of forward-travelling phonons. The resultant atomic motion is
illustrated with model simulations of long atomic wires under current. While the critical current density for
these effects is very high compared with those in electroplasticity phenomena, it is hoped that the paper will
stimulate further research into non-conservative dynamics in extended conductors and the possible relevance
of the effect to electropulsing.