• Proceedings of the Korean Magnestics Society Conference
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• 2012.11a
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• pp.61-62
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• 2012

• Proceedings of the Korean Magnestics Society Conference
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• 2013.12a
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• pp.57-58
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• 2013

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.798-798
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• 2006

• Proceedings of the Korean Magnestics Society Conference
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• 2017.05a
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• pp.146-146
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• 2017

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.134-134
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• 2002

• Journal of the Korean Magnetics Society
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• v.15 no.4
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• pp.241-245
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• 2005

CoFeNi alloys are some of the most studied soft magnetic materials because of their applications as write-head core materials in HDD and MEMS. Ternary CoFeNi films with high saturation magnetic flux density, Bs and low coercivity, He were successfully grown by electrodeposition. The optimal composition was $Co_{30}\;Fe_{34}\;Ni_{36}(at\%)$, and Bs and Hc were 1.9 T and 0.16 A/m, respectively. The XRD and TEM results show that the low Hc of the CoFeNi films was due to very fine crystal particles and mixed fcc and bcc phases.

• Journal of the Korean Society for Railway
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• v.13 no.4
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• pp.404-411
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• 2010

Authors conducted a deduction and characteristic calculation of the some parameters using a magnetic equivalent circuit method to verify a basic design result of a rotary-typed small-scaled linear induction motor for a railway transit. In a LIM, it is possible to express the parameters of the magnetic equivalent circuit into a function of the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. It means that the LIM properties can be changed considerably by the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. So, authors analyzed a tendency of changes of the magnetic equivalent circuit parameters and the LIM characteristics by changing of the airgap, the thickness of the secondary aluminium plate and the overhang length and shape of a rotary-typed small-scaled LIM, and accomplished a basic research to develop a real-scaled LIM for a railway transit.

• Journal of the Korean Magnetics Society
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• v.11 no.3
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• pp.134-140
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• 2001

Flux-gate magnetometer was developed in 1930's, and it has been widely used for the low magnetic field measurements. In this work, we have employed amorphous ribbon 2714A produced by Allied Chem. Co. as sensor core material. To develop low noise, low power consumption, and high reliability flux-gate magnetometer, we have measured ac magnetic properties depending on the annealing conditions. As quenched state amorphous core shows high noise level and ac magnetic properties were changed under the condition of accelerated aging test, but amorphous ribbon, which was annealed under 350 $\^{C}$ during 1 hour, shows low noise level of 0.1 nT in the frequency range of dc∼10 Hz which was 10 times better than the as quenched amorphous ribbon. Under accelerated aging test, ac magnetic properties such as squareness and coercivity of the annealed samples show higher reliability and approached to a certain limiting value as exponential function. We can see that high reliability and low noise flux-gate magnetometer could be developed, if we consider this ac magnetic properties change in the sensor design.

• Journal of the Korean Magnetics Society
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• v.5 no.4
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• pp.304-308
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• 1995

In order to measure magnetic field difference, we have constructed a fluxgate magnetometer which is based on the measurement of apparent coreci ve field strength from the magnetizing current of two sensors. 'Co-based amorphous ribbon, which has square shape of ac hysteresis loop, was used as core material. Two sensors have 315 turns of the primary and the secondary windings respectively, and core size of 2 mm wide and 30 mm long. The primary windings are connected parallel to measure external magnetic field difference and the secondary windings serieally for the averaged magnetic induction of the cores. The constructed magnetometer could measure magnetic field difference with sensitivity of $1.6{\times}10^{6}V/T$ and resolution of 1 nT at 1 Hz bandwidth.

• Journal of the Korean Magnetics Society
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• v.9 no.6
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• pp.285-290
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• 1999

The magnetic properties of sputtered amorphous $Fe_{86.7}Zr_{3.3}B_4Ag_6$ thin films, which contains an additional insoluble element Ag, have been investigated as a function of uniaxal field annealing temperature. The amorphous $Fe_{86.7}Zr_{3.3}B_4Ag_6$ thin films produced by relatively low temperature annealing at 40$0^{\circ}C$ for 1 hour was found to have very high permeability of 7800 at 50 MHz, 0.2 mOe, high magnetization of 1.7 T, low coercivity of 1.0 Oe and very low core loss of 1.4 W/cc at 1 MHz, 0.1 T, respectively. It is notable that the permeability and core loss values for various kinds of the soft magnetic thin films reported up to now. The reason for the appearance for the good soft magnetic properties is presumably due to the homogeneous formation of very fine bcc $\alpha$-Fe clusters with the size in the amorphous $Fe_{86.7}Zr_{3.3}B_4Ag_6$ thin films matrix, which can be deduced from the XRD results.