• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.889-892
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• 2000

We have investigated the Pt doping effect on structural and electrochemical properties of amorphous vanadium oxide film, grown by radio frequency magnetron sputtering. Room temperature charge-discharge measurements based on a half-cell with a constant current clearly indicated that the Pt doping could improve the cyclibility of V$_2$O$_{5}$ cathode film. Using glancing angle x-ray diffraction (GXRD) and high resolution transmission electron microscopy (HRTEM) analysis, we found that the Pt doping with l0W r.f. power induce more random amorphous structure than undoped V$_2$O$_{5}$ film. As the r.f. power of Pt increases, large amount of Pt incorporates into amorphous V$_2$O$_{5}$ and makes PtOx microcrystalline phase in amorphous matrix. This result suggests that the semicondcuting PtOx microcrystalline phase in amorphous matrix lead to a drastically faded cyclibility of 50W Pt doped V$_2$O$_{5}$ cathode film. Possible explanations are given to describe the Pt doping effect on cyclibility of vanadium oxide cathode film.de film.

• Korean Journal of Metals and Materials
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• v.46 no.7
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• pp.403-411
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• 2008

Zr-based amorphous alloy matrix composites reinforced with tantalum continuous fibers were fabricated by liquid pressing process, and their microstructures and mechanical properties were investigated. About 60 vol.% of tantalum fibers were homogeneously distributed inside the amorphous matrix, which contained a small amount of polygonal crystalline particles. The ductility of the tantalum-continuous-fiber-reinforced composite under tensile or compressive loading was dramatically improved over that of the monolithic amorphous alloy, while maintaining high strength. The consequential observation of the tensile deformation and fracture behavior of the composite showed the formation of multiple shear bands and multiple necking, crack deflection in the amorphous matrix, and obstruction of crack propagation by ductile fibers, thereby resulting in very high tensile elongation of 7.2%. These findings suggested that the liquid pressing process was useful for the development of amorphous matrix composites with improved ductility.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.243-246
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• 1997

A new technique for low temperature crystallization of amorphous silicon, called field aided lateral crystallization(FALC) was attempted. To demonstrate the concept of FALC, thin layer of nickel(30${\AA}$) was deposited on top of amorphous silicon film and the electric field was applied during the crystallization. The effects of electric field on the crystallization behavior of amorphous silicon film were investigated.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1677-1679
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• 2007

Thickness dependent morphology of ZnO films was studied, and ZnO can be intentionally grown into amorphous phase by reducing the thickness. The top-gate amorphous ZnO TTFTs with rather high field-effect mobilities and on/off current ratios were effectively fabricated.

• Laser Solutions
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• v.2 no.1
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• pp.43-50
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• 1999

For the conventional welding method. the high heat transfer makes the crystallized zone of the work material unavoidable. Whereas the laser is able to weld the amorphous metal without a crystallized zone, because heat transfer is limited within a very small restricted volume. In this paper, the possibilities and the limits of the laser welding were studied to utilize the advantageous properties of amorphous metal foils.

• Journal of Powder Materials
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• v.7 no.2
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• pp.85-92
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• 2000

The Cu55Ti45 system was effectively mechanically-alloyed using a pulverizer. Noncrystallinities of the powders were characterized by TEM, X-ray and DSC. The amorphous powders were consolidated without losing their noncrystallinities. The consolidating conditions keeping a non-crystalline were obtained by building a TTT diagram of the amorphous powders. The microhardness of the crystallite and bulk amorphous alloys are also compared.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.913-914
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• 2006

Amorphous diamond has a very low work function (1 eV) at modest temperature ($150^{\circ}C$). It has been coat coated on electron emitting electrodes. Such electrodes are used for cold cathode fluorescence lamps (CCFL) that illuminate liquid crystal displays (LCD) for rnote books and television sets. Amorphous diamond can dramatically reduce the turn-on voltage to lit CCFL so the lamp life can be greatly extended. Moreover, the electrical current can be increased to enhance the brightness of the light.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1148-1148
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• 2006

• Journal of the Korean Magnetics Society
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• v.2 no.1
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• pp.29-36
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• 1992

The fundamental research about the amorphous ferrite, which is expected as the important material for electronic and information imdustry in future, was carried out in this work. Because the ferromagnetic amorphous ferrites reported recently are very inferior in magnetic properties than the crystalline ferrites, the development of the more ferromagnetic amorphous ferrites is required. In order to obtain the fundamental data for the preparation of amorphous ferrites, the hand-made twin-roller quenching apparatus was used for rapid quenching. Investigation on amorphous ferrite in the system $CaO-Bi_{2}O_{3}-Fe_{2}O_{3}$ has been carried out in the composition of 10-50 mole% CaO, 10-50 mole% $Bi_{2}O_{3}$, 40-70 mole% $Fe_{2}O_{3}$. Large magnetization values were obtained near the composition of the mixture of $BiFeO_{3}$ and $CaFe_{4}O_{7}$. Especially, an amorphous ${(CaO)}_{20}{(Bi_{2}O_{3})_{15}{(Fe_{2}O_{3})}_{65}$ specimen has a magmetization value of about 21.84 emu/g at 0K(10 kOe). Fe $M\"{o}ssbauer$ absorption spectrum indicates that this specimen is compsed of two amorphous phases, antiferromagnetic phase($\alpha$-phase) and ferromagnetic phase($\beta$-phase). Crystallization of this amorphous ferrite was happened in steps-$550^{\circ}C$ and $775^{\circ}C$, then observed crystal phases were perovskite phase of $BiFeO_{3}$ and $Fe_{2}O_{3}$ phase.

• Journal of Powder Materials
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• v.16 no.5
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• pp.316-325
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• 2009

Fe based (Fe$_{68.2}$C$_{5.9}$Si$_{3.5}$B$_{6.7}$P$_{9.6}$Cr$_{2.1}$Mo$_{2.0}$Al$_{2.0}$) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The experiment results show that the as-prepared Fe amorphous powders less than 90 $\mu$m in size has a fully amorphous phase and its weight fraction was about 73.7%. The as-atomized amorphous Fe powders had a complete spherical shape with very clean surface. Differential scanning calorimetric results of the as-atomized Fe powders less than 90 $\mu$m showed that the glass transition, T$_g$, onset crystallization, T$_x$, and super-cooled liquid range $\Delta$T=T$_x$-T$_g$ were 512, 548 and 36$^{\circ}C$, respectively. Fe amorphous powders were mixed and deformed well with 10 wt.% Cu by using AGO-2 high energy ball mill under 500 rpm.