EROSION FEATURES OF TUNGSTEN SURFACES UNDER COMBINED STEADY-STATE AND TRANSIENT PLASMA LOADS

The paper presents the experimental research on damage of the tungsten surfaces under combined plasma exposures. Steady-state hydrogen exposures (particle flux of 2x10(22) m(-2) s(-1), heat flux of 1.7 MW/m(2), fluence of 10(26) m(-2), average ion energy of 2 keV) were provided by FALCON ion source. The pulsed plasma loads below the tungsten melting threshold (hydrogen plasma streams with surface heat load of 0.45 MJ/m(2) and the pulse duration of 0.25 ms) were performed by means of QSPA Kh-50 device. The behavior of structure, sub-structure and stress-state of tungsten samples have been studied after each cycle of pulsed and steady-state plasma loads.