Fusion Engineering and Design 39–40 (1998) 551–557 Thermal fatigue tests with actively cooled divertor mock-ups for ITER M. Ro ¨ dig a, *, R. Duwe a , C. Ibbott b , D. Jacobson c , G. Le Marois d , A. Lind e , J. Linke a , P. Lorenzetto f , A. Peacock g , L. Plo ¨ chl h , A. Schuster a , Y. Severi i , G. Vieider f , E. Visca j , B. Wiechers a a Forschungszentrum Ju ¨lich GmbH, Association KFA-EURATOM, D-52425 Ju ¨lich, Germany b ITER Joint Central Team, D-85748 Garching, Germany c GMMT Ltd., Borehamwood WD61 RX, UK d CEA Grenoble, F -38054 Grenoble, France e Studsik Material, S -61182 Nyko ¨ping, Sweden f NET Team, D-85748 Garching, Germany g JET Joint Undertaking, Abingdon OX14 3EA, UK h Metallwerk Plansee, A-6600 Reutte, Austria i CEA Cadarache, F -13108 Saint Paul Lez Durance, France j ENEA, I -00044 Frascati, Italy Abstract Mock-ups for high heat flux components with beryllium and CFC armour materials have been tested by means of the electron beam facility JUDITH. The experiments concerned screening tests to evaluate heat removal efficiency and thermal fatigue tests. CFC monoblocks attached to DS-Cu (Glidcop Al25) and CuCrZr tubes by active metal casting and Ti brazing showed the best thermal fatigue behaviour. They survived more than 1000 cycles at heat loads up to 25 MW m -2 without any indication of failure. Operational limits are given only by the surface temperature on the CFC tiles. Most of the beryllium mock-ups were of the flat tile type. Joining techniques were brazing, hot isostatic pressing (HIP) and diffusion bonding. HIPed and diffusion bonded Be/Cu modules have not yet reached the standards for application in high heat flux components. The limit of this production method is reached for heat loads of approximately 5 MW m -2 . Brazing with and without silver seems to be a more robust solution. A flat tile mock-up with CuMnSnCe braze was loaded at 5.4 MW m -2 for 1000 cycles without damage. The first test with a beryllium monoblock joined to a CuCrZr tube by means of Incusil brazing shows promising results; it survived 1000 cycles at 4.5 MW m -2 without failure. © 1998 Elsevier Science S.A. All rights reserved. 1. Introduction The main candidate materials for plasma-facing components in the International Thermonuclear * Corresponding author. 0920-3796/98/$19.00 © 1998 Elsevier Science S.A. All rights reserved. PII S0920-3796(98)00131-8