• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.471-472
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• 2006

High aspect ratio of nano hairs on a plastic substrate is molded using thermoplstic materials including COC, PP, PC and PMMA. As a template for molding nano hairs, AAO membrane is adopted, which is 60um thick and 13mm in diameter. This membrane has about 109 of through-holes of which diameter is around 200nm. This AAO membrane and the pellet of materials are stacked in the mold and pressed to mold after heating up to be melted. The AAO membrane is removed using KOH to obtain the molded nano hairs. As a result, the diameter of the molded hairs is around 200nm and the length is $2um{\sim}60um$ depending on the molding conditions and materials.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.849-852
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• 2006

The lightweight foamed concrete is superior to properties of insulation and light-weight because it is included in many inner pore. So, lightweight foamed concrete used to construction field that need to property of insulation. The property of insulation of lightweight foamed concrete is varied with density. Also, Density is varied with hardening matrix and pore rate. The purpose of the experiment is to know thermal properties of specimen according to the change of density when heating the specimen. As a result of this experiment, the higher density, the lower temperature of mold. this tendency isn't same as ordinary lightweight foamed concrete, and then density 0.9 is expressed most low temperature result also the discontinuity of shape of mold was efficient for the prevention of the temperature rise.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1313-1318
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• 2007

When the mold is cooled suddenly to reduce the time for forming work and improve the quality of jar50ml which is different highly at rib thickness by a series of various curvature radii, the poor quality of void, flow and deformation happens. The structure of spiral cooling circuit at cavity and core can control the temperature of inner and outer side sufficiently. And the system can control cooling and heating automatically. These things are applied to Jar mold. and so, the best quality and the effect of productivity improvement can be obtained.

• Design & Manufacturing
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• v.17 no.3
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• pp.1-7
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• 2023

Blow molding is a manufacturing process in which thermoplastic preforms are preheated and then pneumatically expanded within a mold to produce hollow products of various shapes. The two-step process, a type of blow molding method, requires the output of multiple infrared lamps to be adjusted individually, so the process of finding initial conditions hinders productivity. In this study, digital twin technology was applied to solve this problem. A blow molding simulation technique was established and simulation-based metadata was generated. A response surface ROM (Reduced Order Model) was built using the generated metadata. Then, a dynamic ROM was constructed using the results of 3D heat transfer analysis. Through this, users can quickly check the product wall thickness uniformity according to changes in the control value of the heating lamp for products of various shapes, and at the same time, check the temperature distribution of the preform in real time.

• Transactions of Materials Processing
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• v.20 no.3
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• pp.250-256
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• 2011

Vacuum-assisted thermoforming is one of the critical steps for the successful application of film insert molding(FIM) to parts of complex shapes. If the thickness distribution of the formed film is non-uniform, cracking, deformation, warping, and wrinkling can easily occur at the injection molding stage. In this study, the effects of processing parameters, which include the film heating time, plug depth, plug speed and vacuum delay time, on film thickness distribution were investigated. It was found that the film thickness at the part sidewall decreases with increasing the film heating time and plug depth, but the thickness at the bottom was found to exhibit the opposite behavior. The film thickness of the sidewall was observed to increase at higher plug speed and vacuum delay time of 0 ~ 0.3sec.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.98-100
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• 2002

We developed the Centrifugal Forming Process(CFP) for HTS tube fabrication. The self-designed equipment for CFP is devided into 3 main parts depending on its role and functions. the melting part by heating of high inductive frequency, centrifugal forming part for the tube and efficient microstructure control of Bi2212 phase and molding part for tube detachment after heat treatment. In this paper we will introduce self designed Centrifugal Forming Process for HTS tube fabrication and discuss about the results related mold materials in terms of high Tc superconductor.

• Proceedings of the KAIS Fall Conference
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• 2002.11a
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• pp.243-245
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• 2002

ABS(Acrylonitrile Butadiene Styrene) 수지는 낮은 비중과 전기전도도, 가공성 등 우수한 물리적 성질을 갖는다. ABS 수지 제조방법인 Conventional process와 이를 개선한 MmSH(Momentary mold Surface Heating) injection process로 제조하여 나타나는 도금의 최적 조건을 연구하였다. 탈지, 에칭, Neutralization, Catalyzing, Accelerating의 전처리 과정을 거쳐 pH 변화에 따른 무전해 Ni 도금을 실시한 결과 각 수지 모두 pH7 이상에서 도금속도와 밀착력이 증가하였으나 MmSH injection process로 제작된 ABS 수지보다 Coventional process에서 제작된 ABS 수지의 밀착력이 우수한 경향이 나타났다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.257-260
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• 2000

The composite composed of glass fabric and BMI resin was fabricated using resin transfer molding(RTM) process. it will be used as a supporting plate of transformer coil for high speed train. To develop a RTM process, permeability of preform was measured and resin properties like a viscosity and gellation time were checked. A resin pre-heating system and a mold system were also designed and developed. Using a vacuum-assisted RTM process, the composite supporting plate was successfully fabricated.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.292-295
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• 2004

본 연구에서는 발포사출성형품의 단점인 외관 품질을 개선하기 위해 순간 금형가열방식인 MmSH(Momentary Mold Surface Heating)을 사용하였다. 또한 발포제의 함량에 따른 발포 체의 구조를 살펴보았다. 일반발포사출과 MmSH방식을 사용 발포사출의 표면거칠기를 비교한 결과 표면이 개선된 것을 볼 수 있었고 발포제의 함량에 따른 발포체의 구조는 함량이 증가함에 따라 중량 감소로 셀 수 증가를 보였지만 어느 한계 이후에서는 영향을 미치지 않는 것으로 보여진다.

• Journal of Ocean Engineering and Technology
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• v.23 no.1
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• pp.135-139
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• 2009

In the line heating for the plate forming of a ship's hull, an in line assessment of completion is necessary for an automated production system. In the current curved plate forming process, a fabricated plate is compared to a template that is made in the mold loft and is used for the determination of the heating line for the next step. In this paper, a new method is presented for the in line assessment of completion for curved plate forming. This method uses a 3-D scanner. For the registration of the scanned data for a surface and the target surface, the ICP (Iterative Closest Points) method was adopted. A computer program was developed to carry out the registration, check for similarities, visualize the surface, and control the results. This program was applied to a sample curved plate forming process.