Diffusion of H in Zircaloy-2 and Zr-2.5%Nb rolled plates between 250 °C and 350 °C by off-situ neutron imaging experiments

•H diffusion coefficients in Zr-alloys rolled plates were measured by neutron imaging.•H content was measured with a sensitivity of 5 wt ppm h and ∼40 µm spatial resolution.•In Zircaloy-2, a weak dependence of the orientation in h diffusion was found.•In Zr-2.5Nb, large differences along the rolling and normal directions were observed.•Specific measurements of h diffusion for any (α+β) Zr-alloys orientations are needed.