Improvement of sintered density of Li2TiO3 pebbles fabricated by direct-wet process

The application of Li2TiO3 pebbles (diameter: 0.2–2 mm, density: 80–85%T.D., grain size: <5 μm) was proposed in the Japanese and European blanket design of a fusion reactor. Preliminary fabrication test of Li2TiO3 pebbles by the direct-wet process which had the advantages for the fabrication cost and the reprocessing was carried out to survey the possibility of this process. Then, the Li2TiO3 pebbles were successfully fabricated from the liquid in which used Li2TiO3 pebbles were dissolved. However, sintered density of the pebbles was less than 50%T.D. Therefore, the fabrication processes were re-examined in this study. From the results of re-examination, it became clear that the sintered density was improved by the modifications of the concentration of Li2TiO3 in the liquid, and drying, etc. Additionally, no crack was observed on the surface of Li2TiO3 pebbles as fabricated and the sintered density of Li2TiO3 pebbles reached the design criteria (80–85%T.D.).