氚增殖剂Li4SiO4 陶瓷小球的制备工艺

欧洲和中国聚变堆固态产氚包层（TBM）的氚增殖剂倾向于采用直径0.5～2mm的Li₄SiO₄陶瓷小球填充床。本工作探讨锂陶瓷小球的性能指标设计，研究挤压-滚圆、烧结法制备Li₄SiO₄小球的工艺可行性，测试分析小球的密度、直径、球形度、晶粒尺寸、压碎载荷等性能。研究表明：挤压-滚圆成型、1050℃无压烧结的Li₄SiO₄陶瓷小球密度为90.4%TD，堆积密度为52.9%TD；平均直径为0.95mm，标准偏差为0.15mm；球形度为1.10；平均压碎载荷为18.50N，标准偏差为2.76N；平均晶粒尺寸为14μm；相结构由Li₄SiO₄主晶相、少量Li₂SiO₃和Li₂Si₂O₅等组成。采用优化的挤压 滚圆、烧结工艺可制备出合格的Li₄SiO₄陶瓷小球产品。

Preparation Process of Li4SiO4 Pebbles as Tritium Breeding Materials

Li4SiO4 with a diameter of 0.5 2 mm has been candidated as solid state tritium breeder material for the testing blanket module (TBM) of fusion reactor being developed in Europe and China. Performance designs of Li ceramics pebbles were discussed, extrusion-spheronisation-sintering process of Li₄SiO₄ pebbles were studied, and density, diameter, sphericity, grain size and crush load of pebbles were analyzed and characterized. Li₄SiO₄ pebbles sintered at 1 050 ℃ have a density of 90.4%TD, pebbled bed density 52.9%TD, diameter (0.95±0.15) mm, sphericity 1.10, crush load (18.50±2.76) N, average grain size 14 μm, phase structures of Li₄SiO₄ (main), Li₂SiO₃ and Li₂Si₂O₅. Products of Li₄SiO₄ pebbles can be fabricated by the improved extrusion-spheronisation and sintering processes.