Design and R & D Progress of ITER HCCR TBM development for Fusion Breeding Blanket

Korea has designed a helium cooled ceramic reflector (HCCR) test blanket module (TBM) including the TBM-shield, which is called the TBM-set, to be tested in ITER, a Nuclear Facility INB-174[1]. Under the TBM program, the National Fusion Research Institute (NFRI) is leading and the Korea Atomic Energy Research Institute (KAERI) is collaborated to design and to develop the key technologies with the collaboration of universities, industries. Through the conceptual design review (CDR), its design integrity was successfully demonstrated at the conceptual design level at various loads [1-15]. After CD approval, preliminary design (PD) was started and the progress is introduced in the present study. After PD review and approval, final design and then fabrication will be started. The main purpose of PD is to design the TBM-set according to the fabrication aspect and more detailed design for interfaces with ITER machine, such as installed TBM port plug and frame. With these considering, PD of TBM-set was started. Figure 1 shows the main change of the design parameters for each TBM-set design phase; breeder material was changed Li4SiO4 to Li2TiO3 and it affects the temperature limit and enrichment of the Li-6; Graphite reflector was changed pebble type to block type and it affects the radial dimension of the TBM; as a results of the TBM-set design, the total weight was changed 5.552 tons to 5.124 tons and the limitation of RAFM steel (1.3 ton) was satisfied to be 1.163 tons. Currently, the R&D activities for the development of HCCR TBS were performed in the areas of structural and breeder material development, the fabrication method of a submodule, graphite pebble fabrication, and coating technology for a tritium permeation barrier. The recent design and R&D progress of the HCCR TBS development in Korea are introduced in this paper.