Tritium release behavior from neutron-irradiated Li2TiO3 single crystal

Li2TiO3 single crystals with various grain size (1-2 mm) were used as specimens. After the irradiation up to 4 x 10(18) n/cm(2) with thermal neutrons in JRR-2, tritium release from the Li2TiO3 specimens in isothermal heating tests was continuously measured with a proportional counter. The tritium release in the range from 625 to 1373 K seems to be controlled by bulk diffusion. The tritium effective diffusion coefficient (D-T) in Li2TiO3 was evaluated to be D-T[cm(2)/s] = 0.100 exp(-104[kJ/mol]/RT), 625 K < T < 1373 K. In this temperature region, the tritium effective diffusion coefficients in Li2TiO3 are close to those of Li2O irradiated with thermal neutrons of 4 x 10(16) and 2 x 10(19) n/cm(2). It indicates that the tritium release performance of Li2TiO3 is essentially as good as that of Li2O. (C) 1998 Elsevier Science B.V. All rights reserved.