• 전기의세계
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• v.24 no.6
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• pp.77-84
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• 1975

This paper treats A.C. arc movement in a transverse A.C. magnetic field at atmospheric pressure with the purpose of selecting electrode materials and obtaining detailed data for design of A.C. air circuit breaker, plasma accelerator and plasma jet. Arc velocities in transverse magnetic field are measured by varying arc current, arc voltage, gap length, magnetic flux density and the erosion of electrode surface, which influence arc velocities. The main results are; 1)Arc velocities in transverse magnetic field have different values according to electrodes of various materials and decrease in a descending order of cold cathode, medium cathode and hot cathode. 2)Arc velocities in transverse magnetic field increases with arc current, arc voltage, gap length and magnetic flux densith and on the other hand decrease with the increase of electrode surface erosion. 3)D.C.arc velocity in D.C. magnetic field is higher than A.C. arc velocity in A.C. magnetic field of the same value.

• Transactions on Electrical and Electronic Materials
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• v.1 no.3
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• pp.29-33
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• 2000

The crystallographic and high frequency characteristics of $Fe_{73.9}Cu_{1.0}Nb_{3.5}Si_{14.0}B_{7.6}$ soft magnetic alloys were investigated under magnetic field annealing, The crystallization fraction of annealed samples with longitudinal magnetic fields is higher than that of samples without magnetic field. When the transverse magnetic field is applied, the crystallization fraction does not increases but decreases until $500^{circ}C$. It is found that for samples, the saturation induction are all same with 1.3 T. The coercive field of as-cast samples is 1.03 A/cm, but in annealed samples it decrease from 0.56 to 0.1A/cm with increasing annealing temperature from 400 to $550^{circ}C$. The squareness of annealed samples under transverse magnetic field has a small value than that of both without field and with longitudinal field annealing. It is noted that the magnetic field annealing with transverse direction to amorphous $Fe_{73.9}Cu_{1.0}Nb_{3.5}Si_{14.0}B_{7.6}$ profoundly influenced on the Mossbauer spectra in contrast to that with longitudinal direction and without magnetic field.

• Journal of the Korean Magnetics Society
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• v.4 no.2
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• pp.150-153
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• 1994

Magnetic field annealing method has been used to obtain proper hysteresis loop shapes which are useful to a device using amorphous ribbon. In this study, two pairs of Helmhotz coils were used to apply longitudinal and transverse magnetic field during annealing. For the measurement of coercive field strength noise which depends on magnetic field annealing, Co-based amorphous alloy ribbon $VITROVAC^{\circledR}$ 6030 was used. For the sample which was annealed under dc transverse and dc longitudinal magnetic field, coercive field strength noise was nearly independent of magnetizing frequency ranging from 1 to 100 kHz, but dc transverse and ac longitudinal magnetic fields annealed samples show that the coercive field strength noise decreased in power of magnetizing frequency. When magnetic domain nucleation occurred, the coercive field strength noise increased remarkably and decreased in power of magnetizing frequency.

• Rapid Communication in Photoscience
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• v.4 no.3
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• pp.50-53
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• 2015

$SnO_2$ thin films were deposited on fused silica substrate by pulsed laser deposition under transverse magnetic field. We have explored the effects of magnetic field and ablation laser wavelength on the optical properties of laser-induced plasma plume and structural characteristics of the deposited $SnO_2$ films. Optical emission from the plume was monitored using an optical fiber to examine the influence of magnetic field on the population of the excited neutral and ionic species and their decay with times after laser ablation. Also, we employed photoluminescence, x-ray diffraction, and UV-Vis absorption to characterize $SnO_2$ films.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.798-802
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• 2010

From time-resolved optical emission spectra, we have investigated the effects of a transverse magnetic field on the expansion of a plasma plume produced by laser ablation of a ZnO:$P_2O_5$ ceramic target in oxygen active atmosphere. The emission spectra of $Zn^{+*}$, $P^{+*}$, and $Zn^*$ neutrals in the presence of magnetic field turn out to be considerably different from those without magnetic field. The characteristics of the deposited films grown on amorphous fused silica substrates by pulsed laser deposition (PLD) are examined by analyzing their photoluminescence (PL), X-ray diffraction (XRD), and UV-visible spectra.

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.19-19
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• 2002

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.29-30
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• 2012

• Applied Microscopy
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• v.47 no.1
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• pp.29-35
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• 2017

Transverse magnetic field annealing (TFA) was carried out on $Fe_{73.5}Cu_1Nb_3Si_{15.5}B_7$ nano-crystalline magnetic core with the aim at decreasing coercivity ($H_c$) while keeping high inductance ($L_s$). The magnetic field generated by direct current (DC) was applied on the magnetic core during different selected annealing stages and it was proved that the nanocrystalline magnetic core achieved lowest $H_c$ when applying transverse field during the whole annealing process (TFA1). Although the microstructure and crystallization degree of the nanocrystalline magnetic core exhibited no obvious difference after TFA1 compared to no field annealing, the TFA1 sample showed a more uniform nanostructure with a smaller mean square deviation of grain size distribution. $H_c$ of the nanocrystalline magnetic core annealed under TFA1 decreased along with the increasing magnetic field. As a result, the certain size nanocrystalline magnetic core with low $H_c$ of 0.6 A/m, low core loss (W at 20 kHz) of 1.6 W/kg under flux density of 0.2 T and high $L_s$ of $13.8{\mu}H$ were obtained after TFA1 with the DC intensity of 140 A. The combination of high $L_s$ with excellent magnetic properties promised this nanocrystalline alloy an outstanding economical application in high frequency transformers.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.69-72
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• 2000

AC losses in multifilamentary HTS tapes can be classified to hysteresis loss, coupling loss, and eddy current loss from the viewpoint of their generation mechanism. From the viewpoint of the major magnetic field component generating them, they can be classified to magnetization loss, transport loss, and total loss. Dividing superconductor to fine filaments, twisting filaments bundle and increasing transverse resistivity are effectively reduce magnetization loss and total loss when the external magnetic field is relatively large. Recently, twisted multifilamentary Bi 2223 tapes with pure silver matrix were fabricated and the reduction of magnetization loss was proved experimentally in the parallel magnetic field to the tape wide face. However, when the perpendicular magnetic field is applied, increasing transverse resistivity is required essentially to reduce the AC losses. The transverse resistivity was increased successfully by the introduction of resistive barrier between filaments.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.24-24
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• 2004