Principal scientist, Japan Atomic Energy Research Institute, Ibaraki,
Professor, College of Liberal Arts and Sciences, Okayama University, Okayama,
Pages: 11 Published: Jan 1987
Measurements of the magnetic anisotropy in pure nickel and bcc iron after fast neutron irradiation at 5 K and after successive isochronal anneals at various temperatures between 5 and 320 K were carried out at 4.2 and 77 K for nickel and iron, respectively. The existences of 110-dumbbell-type interstitial configurations in iron and 100-dumbbell-type in nickel have been confirmed. By analyzing the intensity data after isochronal anneals, we found that the clusters of 100-dumbbell interstitials on the (100) planes in nickel transfer onto (111) planes after a 320 K anneal and grow into Frank-type dislocation loops. For iron they are initially aggregated on (110) planes and slip onto (111) planes after a 220 K anneal. Comparing the results of magnetic anisotropy in iron with those in nickel, we have also explained the high migration temperature of interstitials in bcc iron by considering the ferromagnetic condition of the 3d-up and 3d-down spin subbands.
nickel, iron, magnetic anisotropy, interstitial, neutron irradiation, dislocation loop, electronic band structure, 3d-transition metals, ferromagnetic metals
Paper ID: STP33805S