T. A. Scherer, R. Heidinger, D. Strauss, A. Meier,
Forschungszentrum Karlsruhe, Association EURATOM-FZK, D-76021 Karlsruhe, Germany
The talk describes the technical specifications and design guidelines for non-metallic replaceable window assemblies for ITER. All relevant material aspects will be discussed.
Ultra low mm-wave loss CVD diamond window assemblies with loss tangent tan d < 10-4 have been manufactured by special brazing technique. The status of the window design and the brazing technique is reviewed. In a new R&D phase the influence of the brazing material and technique (Ag/Cu and aluminium diffusion bonding) on the performance of the diamond disk will be investigated. Diamond disks from different companies will be compared with respect to the applicability. A first characterisation will be performed by low power RF measurements, pressure tests and thermohydraulic analysis. In collaboration with JAEA high power RF tests are planned to determine the temperature distribution by IR imaging and to investigate arcing processes. For this purpose special modified window assemblies (steel/copper/diamond) will be manufactured.
Implied possible exchanges are proposed with JAEA (K. Sakamoto, K. Takahashi) on design of torus windows for ECH Launchers at ITER (equatorial and upper port plugs) and low and high power testing of window units.