基于蒙特卡罗方法的固态氚增殖剂聚变中子辐照损伤行为分析

实验包层模块(TBM)是聚变反应堆最重要的组件之一,作用是产氚和能量提取。锂陶瓷具有良好的化学稳定性、热机械性能、产氚性能以及可在更高温度下使用等特点,被认为是聚变堆包层最具吸引力的氚增殖剂材料。中国ITER-TBM设计方案采用了氦冷固态氚增殖剂(HCCB)TBM结构,其聚变环境下的辐照损伤行为可为中国HCCB TBM结构设计提供支持。针对固态氚增殖剂聚变中子辐照损伤问题,利用蒙特卡罗模拟,对比分析了Li_4SiO_4和Li_2TiO_3的中子辐照离位损伤和嬗变气体损伤。结果表明:在相同的服役时间下,Li_4SiO_4比Li_2TiO_3将产生更多的嬗变气体,且在高6 Li丰度情况下,其中子辐照损伤也更严重,会产生更高的损伤剂量和更大的损伤截面。但是,嬗变气体所造成的空位损伤Li_2TiO_3要比Li_4SiO_4严重;对两种陶瓷材料来讲,氦损伤效应均强于氚损伤效应。

Monte Carlo Simulation on Neutron Irradiation Damage of Solid Tritium Breeder for Fusion Application

The test blanket module (TBM) with function of tritium production and energy extraction is one of the most important components for a fusion reactor. Lithium-containing ceramics have been recognized as attractive tritium breeding materials for fusion reactor blankets based on their favorable chemical stability, appropriate thermo-mechanical properties, good tritium release performance and application at higher operating temperature,etc. The helium cooled ceramic breeding (HCCB) TBM is selected in Chinese (CN) TBM design. And their irradiation damage behaviors under fusion neutron environment are necessary to be evaluated to support the design criteria for CN HCCB TBM. In this study,the neutron irradiation displacement damage and the transmutation gas damage of Li4SiO4 and Li2TiO3 have been carried out with Monte Carlo simulation. The results demonstrated that more serious damage characteristics,such as more damage dose,larger defect production cross-section in high 6Li enrichment and higher transmutation gas production rate,have been found in Li4SiO4 than that in Li2TiO3 at the same service time. However,the vacancy damage induced by transmutation gas of Li2TiO3 is more severe than that of Li4SiO4 ,and helium induced damage is stronger than that of tritium for both two lithium ceramic breeders.