• 한국표면공학회지
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• 제37권6호
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• pp.319-325
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• 2004

Fe thin films containing Si particles were prepared on metallic substrates by electrodeposition method in sulfate solutions and the content of codeposited Si particles in the films was investigated as a function of applied current density, the content of Si particels in the solution, solution pH, solution temperature and concentration of $FeSO_4$$7H_2$O in the solution. The amount of Si codeposited in the film was not dependent on the applied current density, solution pH and solution temperature, while it was dependent on the content of Si particles in the solution and the concentration of $FeSO_4$$7H_2$O in the solution. The amount of Si codeposited in the film increased with increasing content of Si particles in the solution but reached a maximum value of about 6 wt% when the content of Si particles in the solution exceeds 100 g/l. On the other hand, the content of Si codeposited in the film increased up to about 17 wt% with decreasing concentration of $FeSO_4$$7H_2$O in the solution. These results would be applied to the fabrication of very thin Fe-6.5 wt% Si sheets for electrical applications.

• 한국분말재료학회지
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• 제6권1호
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• pp.96-102
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• 1999

The effect of Pb addition on microstructure and wear resistance was studied in rapidly solidified Al-20Si-5Fe-xPb(x=2, 4, 6 wt.%) alloys. The R/S Al-20Si-5Fe-xPb (x=2, 4, 6 wt.%) alloys showed a fine and homogeneous microstructure and an improved wear property compared with Al-20Si-5Fe alloy, while no significant change in UTS (Ultimate Tensile Strength) was shown. Contribution of the dispersoids on the wear property was discussed by showing the plastic deformation layers formed during wear track.

• 한국진공학회지
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• 제21권5호
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• pp.258-263
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• 2012

펄스레이저 증착법으로 P형 실리콘(100) 기판위에 증착한 Fe 희석된 Si 합금의 구조와 전기적 및 자기적 물성을 연구하였다. 합금시료에 대한 X-선 회절패턴에서 육방정계에 해당하는 FeSi, $Fe_3Si$, 및 $Fe_5Si_3$와 관련된 여러 개의 회절신호가 관측되었으며, 에너지분산분광 측정에 의한 시료내 Fe 원자의 함량은 1.25~6.49 atm, %로 나타났다. 또한, 온도변화에 따른 전기비저항 값의 측정으로부터 5.21 meV와 7.79 meV 두 개의 활성화에너지를 얻을 수 있었다. 절대온도 10 K에서 측정한 최대 자화는 약 100 emu/cc로 나타났으며, 3,000 Oe의 외부자기장하에서 온도의 함수로 측정한 자화 값으로부터 시료의 강자성 특성은 350 K까지도 유지됨을 알 수 있었다.

• 한국주조공학회지
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• 제10권3호
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• pp.225-234
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• 1990

Spheroidal graphite cast irons which are Fe-3%C-(4－6)%Si-(0－0.5)%Mo were studied to improve not only heat resistance but also mechanical properties. With increasing Mo content, the graphitization was decreased and carbide volume fraction was increased. The graphite spheroidization ratio was not decreased in Fe-3%C-6%Si-Mo system cast iron with increasing Mo content, but that was decreased in Fe-3%C-4%Si-Mo system and Fe-3%C-5%Si-Mo system cast irons. Hardness was increased with the Si and Mo contents. At constant Si content, tensile strength was increased with increasing Mo content, but that was decreased at 6%Si. In the experiment of oxidation, weight gain was decreased as the Si and/or Mo content increased, but increased at 1.5%Mo content.

• 대한기계학회논문집A
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• 제25권7호
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• pp.1073-1081
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• 2001

Many researches have published numerous papers about the high-strain-rate obtained from Split Hopkinson Pressure Bar(SHPB) tests. And 6.5wt%Si steel is widely known as an excellent magnetic material because its magnetostriction is nearly zero. Single crystals are prepared by the Floating Zone(FZ) method, which melts the alloy by the use of a high temperature electron beam in a pure argon gas condition. In this paper, the fracture behavior of the poly crystals and single crystals (DO$_3$phase) of Fe-6.5wt%Si alloy by SHPB test is observed. The comparison of high-strain-rate results with static results was done. Obtained main results are as follows: (1) Fe-6.5wt%Si alloy has higher strength at high-strain-rate tensile. SHPB results of polycrystal are twice as high as static results. (2) From the fractography, the cleavage steps are remarkably reduced in the SHPB test compared with the static test.

• 대한기계학회논문집A
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• 제24권12호
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• pp.2909-2916
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• 2000

6.5wt% Si steel is widely known as an excellent magnetic material because its magnetostriction is nearly zero. The AX magnetic properties as magnetostriction of 6.5% Si steel were evaluated and compared with those of conventional 3% Si steel sheet. In this paper, the fracture behavior of the poly crystals and single crystals of Fe-6.5wt%Si alloy has been observed. Single crystals were prepared by Floating Zone(FZ) method, which melts the alloy by the use of high temperature electron beam in pure argon gas condition. And the single crystals were annealed at 500$^{\circ}C$ and 700$^{\circ}C$ respectively and tensile tested at room temperature. According to the result, B2 phase has more good elongation than DO$_3$ phase. It was also found that the fracture surfaces of the single crystals have hairline facets in same direction, and the facets change the direction according to the single crystal phase.

• 한국분말재료학회지
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• 제12권1호
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• pp.24-29
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• 2005

Nano Fe-6.5wt%Si powders have been synthesized by mechano-chemical process (MCP) for an application of soft magnetic core. Owing to hard and brittle characteristics of Fe-6.5Si nano powders having large surface area, it is very difficult to reach high density more than 70% of theoretical density (~7.4 g/$cm_3$) by cold compaction. To overcome such problem a magnetic pulsed compaction (MPC), which is one of dynamic compaction techniques, was applied. The green density was achieved about 78% (~5.8 g/$cm_3$) by MPC at room temperature.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1995년도 춘계연구발표회 논문개요집
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• pp.64-65
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• 1995

• 한국자기학회지
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• 제16권6호
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• pp.276-278
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• 2006

스위칭 특성을 향상시키기 위하여 비정질 강자성 CoFeSiB 자유층을 갖는 자기터널접합 (MTJ)의 스위칭 특성을 연구하였다. 자기터널접합의 구조는 $Si/SiO_{2}/Ta$ 45/Ru 9.5/IrMn 10/CoFe 10/CoFe $7/AlO_{x}/CoFeSiB\;(t)/Ru\;60\;(nm)$이다. CoFeSiB는 $560\;emu/cm^{3}$의 낮은 포화자화도와 $2800\;erg/cm^{3}$의 높은 이방성 상수를 가졌다. 이러한 특성이 자기터널접합의 낮은 보자력($H_{c}$)과 높은 자장민감도를 갖게 한다. 이것은 또한 Landau-Lisfschitz-Gilbert 방정식에 근거한 미세자기 전산시뮬레이션을 통하여 submicrometersized elements에서도 확인하였다. CoFeSiB 자유층 두께를 증가함으로서 스위칭 특성은 반자화 자기장의 증가로 인하여 더욱더 나빠졌다.

• 한국재료학회지
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• 제8권7호
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• pp.584-590
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• 1998

$(Fe_{0.98}Mn_{0.02})_xSi_2(x{\leq$}1) 조성으로, 용융법으로 제조한 $\alpha$-$Fe_2Si_5$상의 잉곳을 730~85$0^{\circ}C$에서 4~20시간 열처리하거나, 기계적 합금화로 제조한 $\varepsilon$-FeSi과 Si상으로 구성된 분말을 760~85$0^{\circ}C$에서 10분간 가압통전소결하므로써 $\beta$-$FeSi_2$기지상에 Si이 분산된 미세조직을 얻을 수 있었다. 조성, 열처리 온도와 소결 온도에 따라 Si 분상의 크기와 간격이 각기 0.05~0.27$\mu\textrm{m}$와 0.2~0.6$\mu\textrm{m}$ 범위에서 변화하였다. 이와 같은 Si 분산상에 의해 $\beta$-$FeSi_2$의 격자 열전도도가 감소되어 성능지수가 향상될 수 있을 것으로 기대된다.