Current status of the innovative basic research on high-temperature engineering using the HTTR

JAERI's High-temperature Engineering Test Reactor (HTTR) aims to further establish and upgrade HTGR technologies as well as the innovative basic research in the field of high-temperature engineering. An overview of the current status of the innovative basic research is briefly described in this paper. Study is concentrated on the three following fields: 1) New materials development. Scientific and technological significance and methods have been investigated for the three following research subjects: neutron transmission doping (NTD) of a high temperature SiC semiconductor, irradiation modification of high-temperature oxide superconductors (HTSC) and research on irradiation damage in heat-resistant ceramic composite materials. 2) fusion-related research. Preliminary tests on surface and functional properties of a solid tritium breeder under irradiation have been carried out to measure ire situ irradiation-induced property changes. This study is concerned with the physicochemical properties of lithium oxide ceramics for the fusion reactor blanket. 3) High-temperature in-core instrumentation development. Efforts have been made to develop optical fibres with heat- and radiation-resistant systems as well as other devices to detect neutron and gamma-ray spectra at high temperatures. JAERI is preparing for the first HTTR irradiation in 2004 and will pursue international collaboration regarding new materials development in the field of high-temperature engineering. (author)