Effects of substitution of Mo for Nb on less-common properties of Finemet alloys

Abstract Particular properties of Fe–Nb/Mo–Cu–B–Si rapidly quenched ribbons were examined. Apart from minor variation, no significant difference due to the Mo for Nb substitution was observed in alloy density and its annealing-induced changes. The same holds for the anisotropic thermal expansion of as-cast ribbon when annealed and for induced anisotropy when annealed under stress. The Mo-substituted ribbons show only slightly higher crystallinity and lower coercivity if annealed in inert gas ambience than in vacuum. Some diversity in surface to interior heterogeneity of the differently annealed ribbons can still be distinguished. Preserving a minor percentage of Nb together with Mo does not seem substantiated to obtain favorable soft magnetic properties of ribbons annealed in inert gas.

[1]  R. Zbořil,et al.  AFM and Mössbauer spectrometry investigation of the nanocrystallization process in Fe–Mo–Cu–B rapidly quenched alloy , 2007 .

[2]  S. Charap,et al.  Physics of magnetism , 1964 .

[3]  A. Gupta,et al.  Rapid stress annealing dependence of structural and magnetic properties of Fe75 − xCoxCu1Nb3Si15B6 alloys , 2008 .

[4]  G. Herzer,et al.  The Influence of Partial Substitution of Nb by Refractory Elements on the Structure and on the Magnetic Properties in Nanocrystalline Soft Magnetic FeBSi-CuNb Alloys , 1993 .

[5]  P. Švec,et al.  Magnetic response of FeNbCuBSi RQ ribbons to bi-axial strain , 2000 .

[6]  E. Illeková,et al.  Unusual magnetic anisotropy of Si-poor FeNbCuBSi alloys , 1998 .

[7]  M. Chromčíková,et al.  Anisotropic thermal expansion of as-cast RQM ribbons and magnetic anisotropy , 2009 .

[8]  J. Borrego,et al.  Nanocrystallization in Fe73.5Si13.5B9Cu1Nb1X2 (X=Nb, Mo and V) alloys studied by X-ray synchrotron radiation , 1998 .

[9]  S. Zwaag,et al.  Accurate Contraction and Creep Measurements During Structural Relaxation of Amorphous Fe40Ni40B20 , 1984 .

[10]  J. T. Wang,et al.  Anisotropy of thermal expansion for amorphous Fe78B13Si9 alloy , 1988 .

[11]  The influence of Cu addition on the crystallization and magnetic properties of FeCoNbB alloys , 2002 .

[12]  P. Švec,et al.  Magnetic properties and macroscopic heterogeneity of FeCoNbB Hitperms , 2008 .

[13]  M. Ipatov,et al.  Magnetic behavior and microstructure of Finemet-type ribbons in both, surface and bulk , 2007 .

[14]  Y. Yoshizawa,et al.  Magnetic properties of FeCuMSiB (M = Cr, V, Mo, Nb, Ta, W) alloys , 1991 .

[15]  P. Švec,et al.  Surface morphology in amorphous Fe-Mo-Cu-B ribbon system , 2007 .

[16]  R. Schäfer,et al.  Influence of heterogeneity on magnetic response of nanocrystalline ribbons , 2003 .

[17]  Liuqing Wang,et al.  Inverter cores using FeMoCuSiB nanocrystalline soft magnetic alloys , 2001 .

[18]  Victorino Franco,et al.  Mo-containing Finemet alloys: microstructure and magnetic properties , 2001 .

[19]  R. V. Major,et al.  Evolution of structure and magnetic properties with annealing temperature in novel Al-containing alloys based on Finemet , 1999 .