On analysis of physical effects on the surface of the electrodes of rail launchers

Summary form only given, as follows. An analysis is performed of the possible occurrence of some physical effects on the surface of electrodes in plasma-armature rail launchers for liner current density higher than critical values. It is shown that the melt on the electrode surface is unstable. An analysis of the possible development of a number of instabilities showed that under experimental conditions, Rayleigh-Taylor and Kelvin-Helmholtz instabilities and magnetohydrodynamic instabilities due to the interaction of the flowing current with the self-magnetic field can develop over times much smaller than the discharge time and can be responsible for supply of the electrode material to the plasma-armature and limitation of the acceleration velocity of solids. X-ray recording of the electrode surface confirmed the presence of small-scale heterogeneity and ejection of the material from the surface. Under certain conditions, the emergence of metal conducting jets from the electrode surface is detected.