Studies of voids in neutron-irradiated aluminium single crystals: II. Small-angle neutron scattering

Abstract

Abstract Absolute small-angle neutron scattering measurements have been made on six aluminium single crystals irradiated with fast neutrons (>0·18MeV) to fluences between 0·3 and 2·0 × 1021 n/cm2. The results are interpreted in terms of the truncated octahedral shape of voids, and are compared with companion transmission electron microscopy and immersion density measurements. The swelling, total void surface area, radius of gyration, and the moment ratios of the size distribution (<D6>)/<D3> and <D3>/<D2>) are in good agreement. These quantities are not only fluence-dependent but also show a marked temperature dependence resulting from the small thermal gradient in the reactor core.