Microstructure and magnetoimpedance (MI) properties of soft magnetic Co73Fe4.5Mn0.5Nb1.0Si4.2B16.8 ribbons with artificial defects have been investigated. The holes of &lt;0.5 mm diameter were created on 5 cm long amorphous ribbon to study the role of demagnetizatizing fields on MI. The MI ratio [MI(%)] decreased by 21% for ribbon with maximum 7 holes. Present results show that the anisotropy induced by artificial defects strongly influences the MI properties. However Joule annealing at an optimum condition enables one to reduce the anisotropy developed by the defects. © 2016 Elsevier B.V.

V. Srinivas

Department Of Physics

Subhendu Kumar Manna

Anisotropy

Defects

Domain walls

magnetic anisotropy

Amorphous ribbon

ARTIFICIAL DEFECTS

DEMAGNETIZING FIELD

Domain wall motion

MAGNETO-IMPEDANCE

Optimum conditions

Soft magnetics

Manganese

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IIT Madras

Journal of Magnetism and Magnetic Materials

Magnetoimpedance (MI) has been investigated in the laser and microwave annealed Fe66Ni7Si7B20 ribbons. The largest MI [(MI)m] values of the ribbons annealed using laser with energies of 150, 200 and 250 mJ/pulse (mJp) are 25% (at 7 MHz), 30% (at 5 MHz) and 21% (at 7 MHz) respectively. The effect of domain wall pinning on MI was observed as field insensitive regions in the MI profiles in the ribbon annealed using 150 mJp energy. Flower shaped grains in amorphous matrix in the ribbon annealed with 200 mJp energy are responsible for highest (MI)m due to the least anisotropy. In the ribbons annealed for 40, 45 and 50 min at 400 °C using microwaves, (MI)m values are 35% (at 5 MHz), 46% (at 6 MHz) and 29% (at 7 MHz) respectively. The large DC conductivity and the least anisotropy (smallest Hk values) in the ribbon microwave annealed for 45 min at 400 °C resulted in (MI)m reaching its highest value in the ribbons investigated. © 2015 Published by Elsevier B.V.

Magnetoimpedance studies on laser and microwave annealed Fe66Ni7si7B20 ribbons

The effect of conventional annealing and Joule annealing on magnetoimpedance (MI) of Co68 Fe5 Si12 B15 ribbons was studied. The ribbons used for the MI measurements were 1 and 5 cm long. The as cast 5-cm-long ribbons exhibit a larger MI compared with the 1-cm-long ribbons, at all frequencies. The maximum MI of the as cast ribbons of 5 cm length is 17% at 600 kHz whereas for the 1-cm-long ribbons it is 3% at 500 kHz. Conventional annealing carried out at 200 and 300 °C for 1 h results in the decrease of the MI in both the 5 and 1-cm-long ribbons, respectively. The Joule annealing of the 5-cm-long ribbons employing a current of 500 mA for 5 min. causes the increase of the MI to 26% at 800 kHz. For the 1 cm Joule-annealed ribbon, employing a current of 500 mA for 5 min., the maximum MI observed is 6% at 500 kHz. © 2006 American Institute of Physics.

Fulltext

Journal of Applied Physics

Effect of length and annealing conditions on magnetoimpedance of Co 68Fe5Si12B15 amorphous ribbons

IEEE Transactions on Magnetics

Improvement of Stepped Magnetoimpedance Properties by Controlling the Demagnetizing Effect

2015 IEEE Magnetics Conference (INTERMAG)

Improvement of stepped magnetoimpedance properties by controlling demagnetizing effect

Magneto-Impedance Biosensor With Enhanced Sensitivity for Highly Sensitive Detection of Nanomag-D Beads

Role of artificially created defects on magnetoimpedance of Co73Fe4.5Mn0.5Nb1.0Si4.2B16.8 ribbon

Journal	Data powered by TypesetJournal of Magnetism and Magnetic Materials
Publisher	Data powered by TypesetElsevier B.V.
ISSN	03048853
Open Access	No