• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.9-14
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• 2001

On the side of that necessity, it is known that the development of Amorphous metal take effects on lowering eddy current loss in a core system. If a amorphous transformer and a motor to which "Amorphous Metal" is applied be widespread, electricity saving should be enormous with the several hundreds billion won of economic effects like cutting the cost of power plants and the unhealthy gases. This paper carried out general evaluation about the characters of Amorphous metal, the expected energy saving effects of a amorphous transformer, the environmental contribution, the increasement of electricity quality, and the features of harmonic.

• 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 the Korea Institute of Building Construction
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• v.12 no.2
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• pp.183-193
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• 2012

Compressive property of high strength concrete with amorphous metal fibers subject to high temperature has been investigated. The measure of this investigation includes explosive spalling, weight loss, residual compressive strength, strain at peak stress, elastic modulus, and residual energy absorption capacity after exposure to $400^{\circ}C$, $600^{\circ}C$and $800^{\circ}C$. In addition to the amorphous metal fiber, two other types of fibers (polypropylene fiber and hooked-end steel fiber) were also included in this investigation for comparison. The experimental program was conducted with high strength concrete using several combinations of the fiber types. The testing result shows that the concrete with amorphous metal fibers plus polypropylene fibers shows a superior behavior than those using other combination or single fiber type ingredient.

• Journal of Navigation and Port Research
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• v.35 no.9
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• pp.717-720
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• 2011

In this paper, we designed and fabricated the Electromagnetic(EM) wave absorber for an Electronic Toll Collection(ETC or Hi-pass) system by using Amorphous metal powder and CPE. The material properties and the absorption properties of the samples containing 50 wt.%, 60 wt.%, 70 wt.%, and 80 wt.% of Amorphous. Moreover, the EM wave absorption abilities were simulated for the different thicknesses of the EM absorbers by adopting the measured permittivity and permeability, and then the EM wave absorber was fabricated based on the simulated design values. As a result, the EM wave absorber with the composition of Amorphous metal powder : CPE = 50 : 50 wt.% with the thickness of 2.6 mm has excellent absorption ability more than 40 dB at 5.8 GHz.

• Laser Solutions
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• v.3 no.2
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• pp.45-51
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• 2000

In this paper, the possibilities and the limits of the laser seam welding were studied to utilize the advantageous properties of amorphous metal foils. For the conventional welding method, the high heat transfer makes the crystallized zone of the work material unavoidable. The laser is able to weld the amorphous metal without a crystallized zone, because heat transfer is limited within a very small restricted volume. The crystallized zone is restricted in the neighbor of welding spot and not in the melting area. This can be proved directly by the etching and indirectly by the tensile shear test, micro hardness test and bending test. The overlapping of welding bead could form the formation of wider and thicker amorphous zone.

• Journal of Welding and Joining
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• v.15 no.3
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• pp.99-108
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• 1997

For the conventional welding method, the high heat transfer makes the crystallization of the work material unavoidable. Whereas the laser is able to weld the amorphous metal without a crystallized zone, because heat transfer is limited withn a very small restricted volume. In this paper, the possibilities and the limits of the laser welding in a deep frozen environment by liquid nitrogen were studied to utilize the advantageous properties of amorphous metal foils. The author investigated, after laser welding in a deep frozen environment with a solid state laser (Nd:YAG-laser), the achievable strengths and the influences of the laser beam parameters on the strengths.

• Laser Solutions
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• v.3 no.3
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• pp.31-37
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• 2000

In this paper, the possibilities of the laser overlap spot welding were studied to utilize the advantageous properties of amorphous metal foils. In order to estimate the usage of amorphous metals foils as structural members, the tensile shear strength and the fracture features were investigated. Although the crystalline zone on the surface was formed, it was not the direct cause of the fracture of the weld. The fracture of the weld resulted from the geometry discontinuity between the workpiece and the protrusion zone, which was formed during the weld process. The vein pattern - the typical feature of the fracture of the amorphous metal - was formed on the fracture surface. The tensile shear stress was reached to 1200 N/㎟ (2-foils overlap welding) and 900 N/㎟ (10-foils overlap welding), whereas the tensile strength of the workpiece was 1500-2000 N/㎟.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.633-636
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• 1992

The need for more efficient transformer core materials, due to increased recognition by the loss reduction of electric utilities, has spurred the development of amorphous metal usage in transformer. The loss of amorphous core is one third to one fourth that of silicon steel at equivalent inductions 15KG and below. Thus, the substitution of amorphous metal for conventional silicon steel in a transformer core can reduce core loss by 75%. This paper describes the development trend, the manufacturing processes of amorphous core transformer and the characteristics of amorphous core transformer in comparison with those of silicon core transformer.

• Journal of the Korean institute of surface engineering
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• v.56 no.2
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• pp.160-168
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• 2023

Recently, investigation on metallization is a key for a stretchable display. Amorphous metal such as Ni and Zr based amorphous metal compounds are introduced for a suitable material with superelastic property under certain stress condition. However, Ni and Zr based amorphous metals have too high resistivity for a display device's interconnectors. In addition, these metals are not suitable for display process chemicals. Therefore, we choose an aluminum based amprhous metal Al-Mo as a interconnector of stretchable display. In this paper, Amorphous Forming Composition Range (AFCR) for Al-Mo alloys are calculated by Midema's model, which is between 0.1 and 0.25 molybdenum, as confirmed by X-ray diffraction (XRD). The elongation tests revealed that amorphous Al-20Mo alloy thin films exhibit superior stretchability compared to pure Al thin films, with significantly less increase in resistivity at a 10% strain. This excellent resistance to hillock formation in the Al20Mo alloy is attributed to the recessed diffusion of aluminum atoms in the amorphous phase, rather than in the crystalline phase, as well as stress distribution and relaxation in the aluminum alloy. Furthermore, according to the AES depth profile analysis, the amorphous Al-Mo alloys are completely compatible with existing etching processes. The alloys exhibit fast etch rates, with a reasonable oxide layer thickness of 10 nm, and there is no diffusion of oxides in the matrix. This compatibility with existing etching processes is an important advantage for the industrial production of stretchable displays.

• Korean Journal of Materials Research
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• v.17 no.11
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• pp.574-579
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• 2007

Amorphous $BaTi_4O_9$ ($BT_4$) film was deposited on Pt/Si substrate by RF magnetron sputter and their dielectric properties and electrical properties are investigated. A cross sectional SEM image and AFM image of the surface of the amorphous $BT_4$ film deposited at room temperature showed the film was grown well on the substrate. The amorphous $BT_4$ film had a large dielectric constant of 32, which is similar to that of the crystalline $BT_4$ film. The leakage current density of the $BT_4$ film was low and a Poole-Frenkel emission was suggested as the leakage current mechanism. A positive quadratic voltage coefficient of capacitance (VCC) was obtained for the $BT_4$ film with a thickness of <70 nm and it could be due to the free carrier relaxation. However, a negative quadratic VCC was obtained for the films with a thickness ${\geq}96nm$, possibly due to the dipolar relaxation. The 55 nm-thick $BT_4$ film had a high capacitance density of $5.1fF/{\mu}m^2$ with a low leakage current density of $11.6nA/cm^2$ at 2 V. Its quadratic and linear VCCs were $244ppm/V^2$ and -52 ppm/V, respectively, with a low temperature coefficient of capacitance of $961ppm/^{\circ}C$ at 100 kHz. These results confirmed the potential suitability of the amorphous $BT_4$ film for use as a high performance metal-insulator-metal (MIM) capacitor.