Hydrogen transport in a niobium-foil assembly under the action of high-temperature hydrogen plasma on a plasma focus setup

The process of hydrogen transport under the action of hydrogen-plasma pulses in the Plasma Focus (PF-4) setup in an assembly of niobium foils with thicknesses of 110 μm each is studied. It is established that the implanted hydrogen is transported to large depths in the Nb foils under the action of the hydrogen plasma. These depths considerably exceed the paths of hydrogen ions from the plasma as the maximum ion velocities are on the order of 10⁸ cm/s. The highest concentration of hydrogen (up to 60 at %) is reached on the surface of the third Nb foil of the assembly. The discovered phenomenon can be explained by the action of shock waves of arising stresses upon the transport and redistribution of hydrogen to considerable depths.