Global Erosion and Deposition Patterns in JET with the ITER-Like Wall
All the tiles removed after the ILW campaigns 2011­2 have been profiled, and results indicate that the primary erosion sites are on limiters near the mid-plane and are likely to have occurred during limiter phases of discharges, as in previous campaigns. There is some correlation between erosion from the inner wall cladding tiles and the Be deposition in the divertor. W is found on all surfaces of the vessel at low concentrations indicating deposition from the plasma and a main chamber source, which may be W-coated CFC tiles since there are also traces of Mo (used as an interlayer for the coatings). Deposited films in the divertor have a layered structure, and every layer shows some W as well as the majority Be, reflecting the impurity composition of the ILW plasmas.