Ferromagnetic domain structures in 65% nickel-35% iron alloys

Abstract

The Kerr magneto-optic effect has been used to observe domain structures on rings of 65% nickel-35% iron after annealing just below the Curie point with and without an external field being present. In general the observations are consistent with the Néel-Taniguchi theory of pair orientation, but measurements of wall movement in the constant-permeability region of the hysteresis loop of the baked alloy do not agree with predictions of theory.

Magnetic domain studies using permeability spectra I

“…It is interesting that the fitted rotational permeability for this material is not much more than twice that for the magnetically annealed specimens : in the magnetically annealed material there should be a strong tendency for domains to be oriented around the ring and so be very much less susceptible (by the rotation mechanism) to the measuring field than a random domain distribution. Jackson and Lee (1969), in a Kerr-effect study of 65-35 NiFe, found a distinct tendency for domains to be oriented around the ring even in material which had been baked in zero field. A lower proportion of 180" walls may be partly responsible for the rather lower wall susceptibility attributed to the baked than to the magnetically annealed specimens.…”

Some observations concerning the use of realistic forces in a microscopic description of the inelastic scattering of nucleons from nuclei at medium energies

“…It is generally assumed to be invalid at [39][40][41][42][43][44] energies lower than 100 MeV; however, there are indications that it might give good results at energies as low as 50 MeV.…”

“…Since A and B are antisymmetr ic states containing n nucleons it follows that <aBJBMB' aj 'm-T-ajm'rlaAJAMA =a M <aBJEME| aj,m,T-10'PJPMP> Ppp x<aPJPMplajmT'aAJAMA> (38) where the complete set of antisymme tric states composed of <aPJPMP|ajmT'aAJAMA>=nl/2<apjp;j T|}aAJA><JPJMPm|JAMA>· (39) Using results (38) and (39) in Eq. (37) and summing over projections gives:…”

Magnetic domains and high permeability in Ni-Fe-Cu-Mo alloys

“…I t has been suggested (Kittel1949) that conventional domains do not exist in very high permeability material. Very little is known about the structure, mainly because the Bitter powder technique is not effective below anisotropy values of approximately 100 J m-3, Domain studies employing the longitudinal Kerr magneto-optic effect have been reported on various nickel-iron alloys (Jackson and Lee 1969) but not in states with vanishingly small K1. Swindell (1964) has measured the magneto-optic rotations for 77% Ni-14% Fe-5% Cu-4 % MO (by weight) material as a function of wavelength and angle of incidence.…”