• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.156-158
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• 2003

Sheets of aluminum alloy 1050 were asymmetrically cold rolled in a rolling mill with different roll speeds. In order to promote the shear deformation during asymmetrical rolling, cold rolling without lubrication was performed. The variation of the shear strain state during asymmetrical rolling was tackled by means of FEM calculations. Asymmetrical rolling gave rise to the development of pronounced residual shear strain gradients throughout the thickness layers.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1992년도 춘계학술대회 논문집 92
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• pp.71-82
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• 1992

The frictional characteristics of Zn-Ni coated steel sheets were investigated by draw bead test and strip draw test. In strip draw test, the frictional characteristics were evaluated by the drawing force ratio (Tc/Ts) for half coating-stripped specimens. It is clarified that the drawing force ratio obtained by strip draw test is a convenient parameter compared to coefficient of friction obtained by draw bead test to evaluate the frictional characteristics of Zn-Ni coated steel sheets.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 자동차부품 제작기술의 진보
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• pp.143-151
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• 1996

In order to reduce the automotive weight, the study exchanging the steel for FRP in leaf spring has been studied. The purposes of this study are to develop more effective manufacturing process of FRP leaf springs than conventional one and to examine the prototype which is made by the developed process. As the results, we have developed more productive manufacturing process by 3-5 times than the conventional one and made FRP leaf spring with equivalent or higher quality than steel.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.262-265
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• 2003

In the present study, subframe was developed using hydroforming technology. The manufacturing process for subframe consists of tube bending, pre-forming and hydroforming. The effects of bending process for manufacturing hydroformed subframe were researched. And the variables of bending process were studied by FEM simulation. The bending method is rotary draw bending that is the most popular, cost-effective bending method for thin walled tubes.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.92-95
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• 2003

Asymmetric rolling of AA1050 Al alloy sheets was performed to obtain the shear textures for improving the deep drawability and the grain refinement. The effect of roll velocity ratio on the texture and the grain refinement of 50％ asymmetrically rolled sheets was studied. The textures of the asymmetrically rolled sheets after annealing at 400$^{\circ}C$ for 1 h was also investigated.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 춘계학술대회논문
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• pp.62-72
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• 1996

A process model is formulated considering the effect of crystallographic testure developed in forming process. The deformation induced plastic anisotropy can be predicted by capturing the evolution of texture during large deformatin in the poly crystaline aggregate. The anisotropic stiffness matrix for the aggregate is derived and implemented in Dulerian finite element code. As an application , the evolution of texture in rolling, drawing and extrusion processes are simulated . The numerical results show good agreement with reported experimental textures.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.244-248
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• 2003

Recently social demands of fuel economy and environmental regulations require the development of light materials and new manufacturing technologies. In this point, the aluminum tube hydroforming process which is satisfied with good strength-to-weight ratio and recyclability is innovative concept. However the level of the aluminum tube hydroforming technology is low in comparison with that of steel tube hydroforming. In this paper, the hydroformability of aluminum tubes in different heat treatments is presented. Theoretical results for forming limits of the wrinkling and bursting are compared with experimental results of aluminum tubes.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1994년도 추계학술대회 논문집
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• pp.157-164
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• 1994

Finite element analysis of material deformation is successfully utilized to understand metal forming processes such as forging, extrusion and deep drawing. However, such analysis involves contact problems; a free node touches a die surface and a contact node slips along the die surface. In the present investigation, appropriate contact algorithms were developed assuming that a three dimensional surface can be divided into bilinear patches and that nodal velocities are linear during an incremental time. The algorithms were coded into a computer program and tested for a simple surface. Comparison of the test result with that obtained from a commercial code is presented and discussed.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.447-451
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• 1999

The plate crown and shape control of plate rolling has become important to obtain not only improved quality but also better yield of products and higher work ratio of rolling. Therefore, the development of a new plate crown and shape control system has been demanded in plate rolling mill. The 3rd Plate Rolling Works of POSCO introduced the new unique system

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.220-226
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• 1999

In automatization of a warehouse for plate products, the selecting control of the number of steel plates to be lifted by a lifting magnet crane and the roller table control of steel plates being transported on are indispensible key technolgies. POSCO had developed these elementary technologies for the product warehouse of the plate mill in Pohang Works and succeeded in making the operation of the large-scale warehouse for plate products.