Torsion-Impedance in Soft Magnetic Amorphous and Nanocrystalline Wires

2012 ◽  
Vol 476-478 ◽  
pp. 1159-1162
Author(s):  
Jian Yong Wang ◽  
Yin Feng Li ◽  
Lan Zhu An ◽  
Su Qin Feng ◽  
Cheng Lin Wang ◽  
...  

The measurements of magneto-impedance,, have been performed, at the frequency f = 1 MHz, on amorphous and nanocrystalline wires under the application of torsion stress ( = 0-125 rad/m). At , exhibit single-peak due to the axial easy direction of the wires. The torsion-impedance,, is defined as the impedance change with at the condition of the axial field H = 0. We found that at the low torsion , shows a maximum at = 0.87 and 5.23 rad/m for the amorphous and the nanocrystalline samples, respectively; with increasing ,of the amorphous wire decreases monotonously and tends to the saturation, but of the nanocrystalline sample shows two more peaks at = 70.65 and 104.67rad/m. These results have been discussed considering the modification of domain structure by the applied torsion.

1997 ◽  
Vol 475 ◽  
Author(s):  
H. Hopster ◽  
Y. Iwasaki ◽  
J. Barthel ◽  
E.B. Maiken ◽  
B.P. Miller ◽  
...  

Abstract Manganese layers were deposited on polycrystalline Fe-based soft magnetic films. The magnetic domain structure of thin Fe overlayers on top these Mn films was measured by secondary electron microscopy with polarization analysis. The Fe layers show spin polarization only beyond a certain critical thickness of about 20 Å. Beyond this thickness the domain structure of the substrate starts to appear in the Fe overlayer. This delayed onset of ferromagnetic order in the Fe layers is attributed to frustration of ferromagnetic order due to the strong coupling to the antiferromagnetically ordered Mn. With increasing Fe film thickness (between 20–30 Å) the magnetization increases and shows the same domain pattern as the substrate. We find that for all Mn thicknesses studied (up to 170 Å) the Fe overlayer domain structure reproduces the substrate domain structure and the magnetization is always aligned parallel with the substrate magnetization.


2013 ◽  
Vol 303-306 ◽  
pp. 2652-2655
Author(s):  
Yin Feng Li ◽  
Pei Ying Chen ◽  
Lan Zhong Li ◽  
Su Qin Feng ◽  
Cheng Lin Wang ◽  
...  

The circular permeability,  =  + j, of a Fe73.5Cu1Nb3Si13.5B9 annealed (500oC, 1 h) amorphous wire was obtained from the measurements of impedance, Z = R + jX = R + jL, as a function of circular magnetic AC field (H = 0.15 – 200A/m) and applied torsion ( = -7.5 – 11.5 rad/m). So the influence of  upon the circular magnetization has been studied. We found that the effects of applied torsion on the circular magnetization can be explained by considering the magneto-elastic interaction and a helical domain structure in the sample. The large change of  with  may be used as a torsion sensor.


1997 ◽  
Vol 174 (1-2) ◽  
pp. 127-132 ◽  
Author(s):  
N Usov ◽  
A Antonov ◽  
A Dykhne ◽  
A Lagar'kov

1997 ◽  
Vol 55 (6) ◽  
pp. R3362-R3365 ◽  
Author(s):  
M. Knobel ◽  
M. L. Sartorelli ◽  
J. P. Sinnecker
Keyword(s):  

1990 ◽  
Vol 26 (5) ◽  
pp. 1403-1405 ◽  
Author(s):  
R. Grossinger ◽  
R. Heszke ◽  
A. Hernando ◽  
O. Mayerhofer ◽  
K.H. Muller ◽  
...  

2011 ◽  
Vol 10 (01n02) ◽  
pp. 301-305
Author(s):  
DEBABRATA MISHRA ◽  
A. PERUMAL ◽  
A. SRINIVASAN

We report the evolution of microstructure, domain structure, and soft magnetic properties of amorphous and nanocrystalline Fe 89-x Zr 11 B x(x = 0 - 10) alloys. High-resolution electron microscopy observations reveal that the annealed alloys exhibit a two-phase microstructure. Addition of B enhances the ferromagnetic properties of Fe – Zr amorphous phase in the two-phase structured microstructure, resulting in good soft magnetic properties. Large-sized domains with smooth domain walls are observed in the alloys annealed below 873 K, which exhibit excellent magnetic softness. On the other hand, in the alloys annealed above 873 K, small-sized domains with irregular domain walls and domain wall pinning by Fe – Zr compound are seen. The soft magnetic properties in Fe – Zr – B alloys not only depend on mean grain size, but also on the strength of the intergranular magnetic coupling and structural inhomogeneities.


2014 ◽  
Vol 802 ◽  
pp. 530-534
Author(s):  
F.A. Nascimento ◽  
M.C.A. da Silva

Deposits of the Fe-6.5wt%Si alloy rapidly quenched by spray forming were investigated. The order phase can be either B2 or DO3 depending on annealing treatment conditions. The observation of pairs dislocations indicates the presence of super dislocations and B2 antiphase boundaries (APBs) which affects significantly the soft magnetic properties. The dislocations bound the APBS which yield δ fringes when image 200 superlattice reflections. Samples treated at 700oC for 1 h were oil quenched, this has induced a decreasing of power loss and the TEM micrographs have showed developed 1⁄4 <111> antiphase domain structure in the B2 phase. The magnetic properties were: power loss of 1.59 W/kg and coercive force of 76 A/m, at B=1 T, f=60 Hz. The samples annealed at 1250°C for 1h showed the same interaction between the APBs but better power losses on their magnetic properties. The magnetic properties were: 1.30 W/kg power loss and 40 A/m coercive force, at same conditions described above. This suggests a strong interaction between magnetic properties and antiphase domain structure in the B2 ordered phase. Optical microscopy observations corroborate the magnetic measurement conclusions.


Sign in / Sign up

Export Citation Format

Share Document