The diffusion of D in 2.5%Nb pressure-tube material was measured with and without neutron irradiation. The results showed that D diffusivity under a neutron flux of some 5 x 1017/m2s was similar to that measured without any flux. This suggested that D diffusivities which were determined from out-of-reactor tests were sufficient for the modelling of D ingress and redistribution.

Influence of Neutron Irradiation on H Diffusion in Zr-2.5Nb Alloy. D.Khatamian, A.Shaddick, V.F.Urbanic: Journal of Alloys and Compounds, 1999, 293-295, 324-8