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Lee, T.K.;Lee, J.E.;Lee, S.K.;Kim, B.M.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2008.10a
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- pp.337-340
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- 2008
The cross section shape of intermediate die is one of important parameters to obtain dimensional accuracy of final product in shaped drawing process. Until now it has been designed by the experience or trial and error of the expert. In this study, the cross section shape of intermediate die fur spline shape is determined by the electronic field analysis, shape factor method. The result of the electronic field analysis, shape factor method has been compared with that of the present method. The effects of cross section shape on the dimensional accuracy were investigated by using FE analysis. And then the multi-stage shaped drawing experiments were performed to verify the results of FE analysis. As a result, the cross section shape from the electronic field analysis had the good dimensional accuracy. The electronic field analysis can be used for the method to obtain the cross section shape of intermediate die in shaped drawing process.
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Park Ho-Sik;Lee Jong-Hoon;Seo Soo-Jung;Lee Young-Kwan;Oh Yong-Soo;Jung Hyun-Chul;Nam Jae-Do
- Macromolecular Research
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- v.14 no.4
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- pp.430-437
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- 2006
The ultra-drawing process of an ultra high molecular weight polyethylene (UHMWPE) gel film was examined by incorporating linear low-density polyethylene (LLDPE) and $BaTiO_3$ nanoparticles. The effects of LLDPE and the draw ratios on the morphological development and mechanical properties of the nanocomposite membrane systems were investigated. By incorporating $BaTiO_3$ nanoparticles in the UHMWPE/LLDPE blend systems, the ultra-drawing process provided a highly extended, fibril structure of UHMWPE chains to form highly porous, composite membranes with well-dispersed nanoparticles. The ultra-drawing process of UHMWPE/LLDPE dry-gel films desirably dispersed the highly loaded $BaTiO_3$ nanoparticles in the porous membrane, which could be used to form multi-layered structures for electronic applications in various embedded, printed circuit board (PCB) systems.
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Lee, J.E.;Lee, T.K.;Lee, S.K.;Kim, B.M.
- Transactions of Materials Processing
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- v.17 no.8
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- pp.627-632
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- 2008
The cross sectional shape of intermediate die is one of important parameters to improve dimensional accuracy of final product in shaped drawing process. Until now, it has been designed by the experience or trial and error of the expert. In this study, the cross sectional shape of intermediate die for spline shape is determined by the electric fields analysis and scale factor method. The result of the electric fields analysis and scale factor method have been compared with that of the expert method. The effects of cross sectional shape on the dimensional accuracy were investigated by using FE-simulation. And then the multi-stage shaped drawing experiments were performed to verify the results of FE-simulation. As a result, the cross sectional shape from the electric fields analysis and scale factor method had the good dimensional accuracy. These two methods can be used for the method to obtain the cross sectional shape of intermediate die in shaped drawing process.
https://doi.org/10.5228/KSPP.2008.17.8.627 인용 PDF KSCI

Lee, S.K.;Kim, M.A.;Ko, D.C.;Kim, B.M.
- Transactions of Materials Processing
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- v.15 no.7 s.88
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- pp.518-523
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- 2006
Wet wire drawing of brass coated steel wire, used for tire reinforcement, is realized with Tungsten Carbide(WC) dies sintered with a cobalt(Co) binder. Dies wear represents an important limitation to the production process and cost savings. Several parameters, such as Co content, WC grain size of tungsten carbide, sintering conditions, and so on, affect on the wear of the drawing die. In this study, the effect of the diamond abrasive particle size on the life of the WC centered dies of the wet wire drawing was investigated. Wet wire drawing experiments were carried out on a wet wire drawing machine. From the experiments, the dies life, dies fracture, wire surface roughness, and wire breaks were investigated. From the results, it was found that the wear of the WC dies increased with the increase in the diamond abrasive particle size.
https://doi.org/10.5228/KSPP.2006.15.7.518 인용 PDF KSCI

Lee, C.W.;Ko, Y.G.;Shin, D.H.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2009.05a
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- pp.409-412
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- 2009
A study is made to put forward the new method of continuous-shear drawing (CSD), and investigate deformation behavior and microstructure evolution of aluminum alloy with a comparison of equal-channel angular (ECA) drawing. In contrast to ECA drawing, the die for CSD deformation can impart an additional strain to the workpiece since the diameter of the exit channel is narrower than that of its entrance channel. Although no significant crack occurs in all conditions during deformation, the sample deformed via CSD method showed better surface quality as compared to ECA drawing. This is mainly ascribed to the fact that the sample is significantly bent rather than sheared when deforming through ECA drawing.
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