The effects of low-flux neutron irradiation at room temperature, upon the mechanical dynamic spectroscopy of 4N-purity material, were studied. A new damping peak appeared at about 730K in irradiated polycrystalline samples. It was absent from non-irradiated and monocrystalline specimens. This peak was attributed to a cooperative mechanism between grain boundary sliding, dragging of point defects which followed dislocation lines, and the stress-assisted breakaway of dislocations from pinning points which were generated by irradiation.

O.A.Lambri, G.I.Lambri, M.E.Torio, C.A.Celauro: Journal of Physics - Condensed Matter, 1996, 8[49], 10253-61