Evaluation of the cool-down behaviour of ITER FW beryllium tiles for an early failure detection

The design of the first wall in ITER foresees several hundred thousand beryllium tiles, which are bonded to the water-cooled CuCrZr supporting structure. Due to the nature of a Tokamak reactor this bonding is faced to thermal fatigue. Since the failure of a single tile might already have a major impact on the operability of ITER, comprehensive high heat flux tests are performed on prototypes prior to the acceptance of manufacturing procedures. For a deeper understanding of the temperature curves, which were and will be measured by IR devices of these first wall prototypes, thermo-mechanical FEM simulations shall demonstrate the possibilities of an early bonding failure detection. Hereby, the maximum temperatures for each cycle as well as the cool-down behaviour are the input data.