Damage of chrome-manganese steels by pulsed fluxes of ions and dense plasma under their separate action on the material in the plasma focus setup

Abstract

Two methods of temporal and spatial separation of the fluxes of hot plasma and fast ions in the Plasma Focus setup are experimentally investigated. In the first case, in a traditional geometry of the experiment, different distances from the focus to the target are used. Ion and plasma fluxes are generated at different instants, move with different velocities, and fall normally to the surface of the target (a chromium-manganese specimen). In this case, the processes of melting and evaporation are accompanied by implantation of plasma-forming gas ions and redistribution of elements in the surface layer. In the second case, separation of plasma and ion fluxes takes place inside the cavity of an extended steep pipe owing to different transport mechanisms of the quasi-neutral plasma and the beam of fast ions. This method allows distinguishing an ion flux of a higher power density (∼109–1010 W/cm2) in the pulse discharge. The damage to the outer pipe surface is found to monotonically decrease with an increase in the distance from the focus, while that along the inner surface is nonmonotonic. The reasons for the abnormally high damage to the ring domain of the inner surface of the pipe by a high-energy ion flux are discussed.