• Transactions of Materials Processing
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• v.10 no.5
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• pp.373-382
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• 2001

Die design by computer simulation has some advantages compared with the conventional method which has performed by designer's experiences and trials and errors. The die filling and solidification process of thixoforming process were simulated by MAGMAsoft/thixo module. Furthermore, the die design for thixoforming was performed with the various geometry shape. The effect of designed gate dimension on filling phenomenon was estimated by filling simulation. The calculated results was compared with experimental data. The free surface phenomenon obtained by experiment have good agreement with computer simulation results. The solidification effect much as prosity and shrinkage for designed semi-solid forging die had been predicted by computer simulation. The designed die for semi-solid forging had been applied to produce of the frame part which is used to airconditious system.

• Journal of Korea Foundry Society
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• v.24 no.6
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• pp.347-355
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• 2004

In the die casting process, the flow of liquid metal has significant influence on the quality of casting products and die life. For the optimal process design of automobile gear housing, various analyses were performed in this study by using computer simulation code, MAGMAsoft. The simulation has been focused on the molten metal behaviors during the mold filling and solidification stages for the sound casting products. Also the internal defects were predicted by application of air pressure and feeding criteria.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.8-11
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• 2007

The new technologies in mobile display developed in SEC are briefly reviewed. For a differentiation, SEC's LTPS line is based on SLS (Sequential Lateral Solidification) technology. In this paper, the characteristics of SEC's SLS in recent and future mobile displays were discussed. The microstructure produced by SLS crystallization is dependent on SLS process conditions such as mask design, laser energy density, and pulse duration time. The microstructure and TFT (Thin Film Transistor) performance are closely related. For an optimization of TFT performance, SLS process condition should be adjusted. Other fabrication processes except crystallization such as blocking layer, gate insulator deposition and cleaning also affect TFT performance. Optimized process condition and tailoring mask design can make it possible to produce high quality AMOLED devices. The TFT non-uniformity caused by laser energy density fluctuation could be successfully diminished by mixing technology.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.11
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• pp.122-128
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• 2000

In this paper, a bulging condition which affect the quality of continuous casting steel was analyzed by using the numerical analytic method. First, solidification analyses were performed for each cooling zone by one-dimensional finite difference method. The bulging deformation of cast slab has been calculated with a two-dimensional elasto-plastic and creep finite element model. The adequacy of the model has been checked against the experimental results. From this study the effects of the process variables such as casting speed, cooling condition and roll pitch were examined. The results from these analyses would be able to apply to the design of continuous casting process.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.83-90
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• 2017

The pyroprocessing of spent nuclear fuel generates LiCl-KCl eutectic waste salt containing radioactive rare earth nuclides. It is necessary to develop a simple process for the treatment of LiCl-KCl eutectic waste in a hot-cell facility. In this study, capture and solidification of a rare earth nuclide (Nd) in LiCl-KCl eutectic salt using an inorganic composite with a $Li_2O-Al_2O_3-SiO_2-B_2O_3$ system was conducted to simplify the existing separation and solidification process of rare earth nuclides in LiCl-KCl eutectic waste salt from the pyroprocessing of spent nuclear fuel. More than 98wt% of Nd in LiCl-KCl eutectic salt was captured when the mass ratio of the composite was 0.67 over $NdCl_3$ in the eutectic salt. The content of $Nd_2O_3$ in the Nd captured-composite reached about 50wt%, and this composite was directly fabricated into a homogeneous and chemical resistant glass waste in a monolithic form. These results will be utilized in designing a process to simplify the existing separation and solidification process.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.192-193
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• 2018

• Journal of Korea Foundry Society
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• v.14 no.3
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• pp.248-257
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• 1994

Research in heat transfer and solidification commonly involves experimentation and mathematical modeling with associated numerical analysis and computation. Inverse problems in heat transfer are part of this paradigm. During the solidification of metal casting, an interfacial heat transfer resistance exists at the boundary between the casting and the mold, and this heat transfer resistance usually varies with time. In the case of the squeeze casting the contact heat transfer resistance is decreased by pressure and ideal contact is almost accomplished. In the present work, heat transfer coefficient, which is inverse value of the heat transfer resistance, was used for convenience. A numerical technique, Non-Linear Estimation has been adopted for calculation of the casting/mold interfacial heat transfer coefficient during the squeeze casting process. In this method, the measured temperature data from experiment were used. The computational results were applied to the analysis of heat transfer and solidification.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.1
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• pp.86-91
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• 2007

Contact material is widely used as electrical parts. Ag-CdO has a good wear resistance and stable contact resistance. But the disadvantages of Ag-Cd alloy are coarse Cd oxides and harmful metal, Cd. Then Ag-Sn alloy that has stable and fine Sn oxide at high temperature has been developed. In order to investigate the effect of Te additional that affects the formation of the oxide layer on the surface and the formation of oxide in matrix Ag, we studied the microstructures and properties of Ag-Sn-In(-Te) material fabricated by rapid solidification process. The experimental procedure were melting using high frequency induction, melt spinning, and internal oxidation. Specimens were examined and analyzed by Transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS) and Vickers hardness. As a result, internal oxidation was completed even at $600^{\circ}C$. Te forms coarse $In_{2}TeO_{6}$ phase and makes fine and well dispersed $SnO_{2}$ Phase. 0.3 wt% Te shows favorable properties.

• Environmental Engineering Research
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• v.23 no.2
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• pp.189-194
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• 2018

The traditional gold mining in Kulon Progo district, Special Region of Yogyakarta Province produced tailings containing mercury (Hg) from the gold amalgamation process. Mercury accumulated in tailings has 164.19 mg/kg - 383.21 mg/kg in total concentration. Stabilization/solidification (S/S) is one of the remediation technologies to reduce waste pollution. Portland cement is one of the additive materials in S/S that effective encapsulates heavy metal waste. The aim of this research is to know the optimum composition of tailings mixture with Portland cement in S/S process. This research used variation of tailings composition. Variation of Portland cement composition with tailing are 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80 and 10:90. The result of this study found that the optimum composition of Portland cement: tailings was 10:90, with compression test of $257ton/m^2$ and TCLP test was 0.0069 mg/L. The compression test results were in accordance to US EPA Standard quality of $35ton/m^2$. TCLP test results meet the standard of Indonesian Government Regulation No. 101 Year 2014 of 0.05 mg/L.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.386-391
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• 1999

The charge-discharge, the high-rate dischargeability, and the self discharge characteristics of the electrodes composed of rapidly solidified ZrV\ulcornerMn\ulcornerMo\ulcornerNi\ulcorneralloy, which has the form of partial substitution of Mn, Mo, Ni for V in $ZrV_2$ were studied. The alloys were prepared using Arc & RSP(Rapid Solidification Process) at the rotating roller speed of 2000 and 5000 rpm. Some of them were received heat treatment at$ 560 ^{\circ}C$ for 1 hour after the solidification to investigate the effect of the heat treatment. It was fond that cycle life was significantly improved by RSP, whereas discharge capacity, activation rte and high rate dischargeability were decreased compared with the conventional arc melting method. The capacity loss seems to be due to the loss of the crystallinity and the increase of the cycle life ascribed to the presence of the amporphous phase as well as the refined grain size of less than 0.2$\mu\textrm{m}$. Heat treatment of the alloy cooled at 2000 rpm improved the cycle life. In case of the alloys cooled at 5000 rpm, both the discharge capacity and the activation rate were significantly improved by the heat treatment.