Experimental modelling of plasma-graphite surface interaction in ITER

The investigation of graphite erosion under normal operation ITER regime an d disruption was performed by means of exposure of RCT graphite samples in a stationary deuterium plasma to a dose of 10(22) cm(-2) and subsequent irr adiation by pourer (250 MW/cm(2)) pulse deuterium plasma how imitating disr uption. The stationary plasma exposure was carried out in the installation LENTA with the energy of deuterium ions being 200 eV at target temperatures of 770 degrees C and 1150 degrees C, The preliminary exposure in stationar y plasma at temperature of physical sputtering does not essentially change the erosion due to a disruption, whereas exposure at the temperature of rad iation enhanced sublimation dramatically increases the erosion due to disru ption. In the latter case, the depth of erosion due to a disruption is dete rmined by the depth of a layer with decreased strength. (C) 1998 Elsevier S cience B.V. All rights reserved.