The Nanocrystallization Processes、Reorientation of the Magnetic Moments and Giant Magneto-impedance Effect of FeCuNbSiB Multilayered Films
|School||East China Normal University|
|Course||Condensed Matter Physics|
|Keywords||FINEMET X-ray diffraction M(?)ssbauer spectrum magnetic moments GMI effect|
The FeCuNbSiB films are prepared by RF magneto-sputtered equipment in this paper. The investigation of the nanocrystallization, magnetic properties and the giant magnetic impedance effect of FeCuNbSiB films is presented in this paper. The main results are listed as below:1.The XRD results showed that the films begin to crystallize at 400℃. After annealing at 510℃, a bcc phase with fine grains of namometer size was observed. By the Scherrer formula, it can be estimated the nano size diameter is from 10 nm to 20 nm at the annealing temperature 510 ℃ ~ 570℃.2.The nanocrystalline volume fraction of the samples and the orientation of the magnetic moments could be obtained by the Mossbauer spectrum. The volume fraction of nanocrystalline phase in the samples annealed at 450℃, 510℃, 540℃ and 570℃ are 67%, 77%, 82% and 89%, respectively. From as-deposited state to the sample annealed at 570°℃, the magnetic moments of the films were orientated from the initial direction parallel to the film plane to the direction perpendicular to it, and later back. Eventually, moments orientations of the film samples were random.3. The GMI ratio of the multilayered films varies with changing orientation of magnetic moments. When the orientation of moments was perpendicular to the film plane, the GMI ratio decreased dramatically.