There are plans at ASDEX Upgrade to cover the heat shield of the inner main chamberwall with tungsten coated graphite tiles. Four tiles were installed at different poloidalpositions of the heat shield and removed after a full experimental campaign. The tiles wereanalysed by means of Rutherford backscattering (RBS) analysis before insertion and byboth RBS and particle induced X ray emission after removal. This is an investigation of the poloidal and toroidal erosion profiles on the tiles due to sputtering bycharge exchange neutral and ion impact.
Impurity behaviour in the ASDEX Upgrade divertor tokamak withlarge area tungsten walls