Local atomic and magnetic structures of amorphous Fe1-xBxalloys studied by neutron scattering

The local atomic and magnetic structures of the ferromagnetic Fe x B 1-x amorphous alloys, where x=0.14, 0.17 and 0.25, have been studied by neutron scattering using pulsed spallation neutrons. The atomic and magnetic structures have been separately determined by applying a magnetic field (5 kOe) parallel and perpendicular to the scattering vector Q. The Fe-Fe, Fe-B and B-Fe coordination numbers could be determined from high-Q measurements (Q max approximately=25 AA -1 ). The results show that there is no significant structural change in Fe 1-x B x amorphous alloys with 0.14<or=x<or=0.25. The magnetic moments reside mainly on Fe atoms. These results give experimental support to the idea that the Invar effect of these alloys can be interpreted in terms of the electronic structure of the alloys. A comment is given for the method of determining the magnetic structure.