embrittlement resulting from bombardment with neutrons, usually encountered in metals that have been exposed to a neutron flux; in steels is evidented by rise in the ductile-to-brittle transistion (see: embrittlement), metallide korral nende haprumine neutronkiirtega pommitamise tulemusena; nt teraste korral täheldatakse külmaprumisläve tõusu (vt haprumine)