Deuterium Retention in SiC-Coated Graphite Tiles of EAST

Fuel retention and recycling in plasma facing materials is a crucial issue for fusion devices, especially for the long pulse discharge devices. In this work, the deuterium retention and the surface erosion of SiC-coated graphite tiles exposed to EAST plasmas have been studied by post-mortem analyses, i.e., thermal desorption spectroscopy (TDS), secondary ion mass spectroscopy (SIMS) and scanning electron microscopy (SEM). The results show that the sample cut from the high field side (HF) tile has been intensely eroded due to deuterium bombardment on plasma facing surfaces in the initial phase of discharges and trapped highest amount of deuterium. Lower deuterium retention has been found in the inner divertor sample, which is presumably due to the particular exposure history in the 2010 spring campaign.