Fabrication and characterization of Li-enriched LiTiO pebbles for a high Li-burnup irradiation test
Tsuchiya, Kunihiko ; Kawamura, Hiroshi
Lithium titanate (LiTiO) pebbles are considered to be a candidate material of tritium breeders for fusion reactor from viewpoints of easy tritium release at low temperatures (about 300) and chemical stability. In the present study, trial fabrication tests of Li-enriched LiTiO pebbles of 1mm in diameter were carried out by a wet process with a dehydration reaction, and characteristics of the Li-enriched LiTiO pebbles were evaluated for preparation of a high Li-burnup test in a testing reactor. Powder of 96at% Li-enriched LiTiO was prepared by a solid state reaction, and two kinds of Li-enriched LiTiO pebbles, namely un-doped and TiO-doped LiTiO pebbles, were fabricated by the wet process. Based on results of the pebble fabrication tests, two kinds of Li-enriched LiTiO pebbles were successfully fabricated with target values (density : 80-85%T.D., grain size : 5m, diameter : 0.85-1.18mm). Physical, chemical and mechanical properties of these pebbles were also evaluated before neutron irradiation tests. Sphericity of these LiTiO pebbles was a satisfying value of about 1.05. Contact strength of these pebbles was about 6300MPa, which was almost the same as that of the LiTiO pebbles with natural Li.