Design factor using a SiC/SiC composites for core component of gas cooled fast reactor, 2; Thermal stress

SiC/SiC複合材料を用いるガス冷却高速炉の炉心部材の設計要素,2; 熱応力

Lee, J.-K.; 永沼 正行  

Lee, J.-K.; Naganuma, Masayuki

ガス冷却高速炉(GFR)の炉心要素の材料としてセラミックスが期待される中、特に炭化ケイ素繊維強化炭化ケイ素(SiC/SiC)複合材料は優れた熱的特性を持っている。SiC/SiC複合材料をGFRの被覆管として採用するためには、使用環境においての応力に対する評価が必要である。そこで、本研究はGFR環境を想定し、SiC/SiC複合材料の熱伝導度変化を予想して熱応力を評価した。さらに、材料特性が被覆管設計に及ぼす影響を考察した。

Core component of GFR (Gas cooled Fast Reactor) will be placed in a harsh environment of high pressure, high temperature and high fast neutron irradiation. Silicon Carbide (SiC) is promising material due to the good heat resistance and low activation. Hence, the effects of thermal conductivity degradation for thermal stress were calculated. In the GFR of present work, pin type fuel using SiC/SiC composite cladding tube was applied. Feasible mechanical properties and thermal conductivity decreasing caused by high temperature neutron irradiation at reactor circumstance are modeled tentatively from reported result in literature. The results affected the core design such as fuel pin specification and linear heat rating. Furthermore, outline of nuclear properties based on present work was discussed.