J. Phys. IV France
Volume 08, Numéro PR2, June 1998
Soft Magnetic Materials 13
Page(s) Pr2-39 - Pr2-42
Soft Magnetic Materials 13

J. Phys. IV France 08 (1998) Pr2-39-Pr2-42

DOI: 10.1051/jp4:1998208

Magnetic and structural properties of nanocrystalline ultrathin Fe83Cu1Nb7B9 submitted to Joule heating

P. Tiberto1, F. Vinai1, P. Allia2, M. Baricco3, J.Y. Park4 and K.Y. Kim4

1  Istituto Elettrotecnico Nazionale Galileo Ferraris, 10125 Torino, Italy
2  Dipartimento di Fisica, Politecnico di Torino, 10129 Torino, Italy
3  Dipartimento di Chimica IFM, Universita di Torino, 10125 Torino, Italy
4  Division of Metals, Korea Institute of Sciences and Technology, Korea

Ultrathin (- 10 µm) ribbons of the amorphous alloy Fe83CU1Nb7B9 obtained by single roll melt spinning have been submitted to do Joule heating in vacuo in order to develop a nanocrystalline phase characterised by a very reduced grain size. The initial permeability of the nanocrystallized alloy was measured on open samples by means of a conventional fluxmetric technique with air-flux compensation. The interval of magnetising frequency was 100 Hz - 10 kHz. All samples were submitted to X-ray diffraction to evaluate the mean grain size, composition and strain level of the nanocrystalline phase. A substantial improvement in the magnetic permeability of Joule-heated nanocrystalline samples with respect to the conventionally annealed ones has been always found. Variations as high as 1000 times the as-quenched value have been observed for a wide range of electrical-current densities (4.107 ≤ j ≤ 6.107 A/m2).

© EDP Sciences 1998