Author(s)

Jozef Sitek, Jarmila Degmová, Katarína Sedlačková, Július Dekan

Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Bratislava, Slovakia.

Amorphous and nanocrystalline (Fe_1–xNi_x)₈₁Nb₇B₁₂ (x = 0, 0.25, 0.5, 0.75) alloys were measured by M?ssbauer spectrometry in the weak external magnetic field of 0.5 T. From structural analyses, ferromagnetic bcc-FeNi and fcc-FeNi and paramagnetic (Fe-Ni)₂₃B₆ phases were identified in the annealed samples. It was shown that in the external magnetic field the intensities of the 2nd and the 5th lines (A₂₃ parameter) are the most sensitive M?ssbauer parameters. Rather small changes were observed in the values of internal magnetic field. Our results showed that the amorphous precursor is more sensitive to the influence of external magnetic field than the nanocrystalline alloy. All spectra of amorphous precursor showed the increase of A₂₃ parameter and decrease of internal magnetic field values of about 1 T (±0.5 T) under influence of external magnetic field. In the case of nanocrystalline samples the tendency for the values of internal magnetic field is similar but the effect is not so pronounced. The measurements confirmed that even weak external magnetic field affected orientation of the net magnetic moments. Our results indicate that effect of the external magnetic field is stronger in the case of amorphous samples due to their disordered structure.

Mössbauer Spectroscopy; Nanocrystalline Fe-Ni Alloy; Soft Magnetic Materials

J. Sitek, J. Degmová, K. Sedlačková and J. Dekan, "Mössbauer Spectroscopy of Fe-Ni-Nb-B Alloy in Weak Magnetic Field," Journal of Modern Physics, Vol. 3 No. 3, 2012, pp. 274-277. doi: 10.4236/jmp.2012.33038.