Аннотация
Mössbauer investigations of radiation damaged zones around 57Co (57Fe) primary knock-ons (PKA) are carried out on Ni3Fe irradiated with 30 MeV protons and 40 and 50 MeV α-particles. The hyperfine field on PKA is found to be much higher than its possible values on 57Fe in Ni3Fe; this fact is interpreted as enrichment of the damaged zones by Fe atoms. It is shown that NiFe precipitates with radius r ≧ 2.6 nm may be stable in Ni3Fe. After a prolonged holding of the proton irradiated specimens their ordering into Ni3Fe superstructure with simultaneous ordering of the precipitates into NiFe is observed. The stoichiometry disturbance of the alloy matrix in the damaged region is explained by atomic separation of the alloy components.