Design requirements for SiC/SiC composites structural material in fusion power reactor blankets

Abstract

This paper recalls the main features of the TAURO blanket, a self-cooled Pb-17Li concept using SiC/SiC composites as structural material, developed for FPR. The objective of this design activity is to compare the characteristics of present-day industrial SiC-SiC composites with those required for a fusion power reactor blanket and to evaluate the main needs of further R&D. The performed analyses indicated that the TAURO blanket would need the availability of SiC/SiC composites approximately 10 mm thick with a thermal conductivity through the thickness of approximately 15 Wm − 1 K − 1 at 1000°C and a low electrical conductivity. A preliminary MHD analysis has indicated that the electrical conductivity should not be greater than 500 V − 1 m − 1 . Irradiation effects should be included in these figures. Under these conditions, the calculated pressure drop due to the high Pb-17Li velocity (approximately 1 m s − 1 ) is much lower then 0.1 MPa. The characteristics and data base of the recently developed 3D-SiC/SiC composite, Cerasep ® N3-1, are reported and discussed in relation to the identified blanket design requirements. The progress on joining techniques is briefly reported. For the time being, the best results have been obtained using Si-based brazing systems initially developed for SiC ceramics and whose major issue is the higher porosity of the SiC/SiC composites.

Spherical torus concept as power plants—the ARIES-ST study

“…This design borrows features of both the EU dual-coolant DEMO blanket [31] and the PbLi-cooled SiC composite blanket, 'TAURO' [32]. The ARIES-ST blanket includes several innovative design features that lead to a new class of attractive blanket systems for fusion power plants: blankets with coolant outlet temperature higher than the maximum structure temperature and using advanced Brayton cycles.…”

“…The maximum interface temperature between the two materials is below 700 8C. Tests at ISPRA have shown that the two materials are compatible at 800 8C under stagnant conditions [32]. Tests in flowing PbLi are under way to better establish operating temperature limits.…”

Observation and simulation of indentation damage in a SiC–SiCfibre ceramic matrix composite

“…SiC-SiC fibre ceramic matrix composites are candidate materials for high temperature fuel cladding in Generation IV gas-cooled nuclear reactor concepts; they have also been proposed for accident-tolerant fuel cladding for current (Gen II/III) light water reactors and have potential applications in the breeder blanket of nuclear fusion power [1,2,3,4]. The influence of microstructure on fracture resistance in these materials is significant, and for this reason microstructure needs to be introduced into predictive modelling of structural integrity.…”

Mechanical and thermal properties of chemical vapor infiltration engineered 2D-woven and 3D-braided carbon silicate composites

“…SiC f /SiC composites have been considered in the design of nuclear reactors in the USA, Japan and EU, such as the ARIES-AT [4], DREAM [5] and TAURO [6]. SiC f /SiC composites were also considered for "first wall" structure in PROMETHEUS IFE reactor [7] and, in China, SiC f /SiC composites are planned for use as control rod shroud tubes in Thorium Molten Salt Reactors (TMSR).…”