• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.101-101
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• 2004

초미세 발포 플라스틱(MCPs; Microcellular Plastics)공정은 기존 발포 플라스틱의 장점을 보존하면서도 그 동안 발포 플라스틱의 단점으로 지적되어온 충격강도, 인성, 경도 등의 기계적 특성저하를 개선하기 위하여 개발되었다. 플라스틱 내에 지름 수 십 $\mu\textrm{m}$ 내외의 기포를 $10^{9}$-$10^{15}$cel1/㎤의 밀도로 발생시키는 초미세 발포공법은 내부의 미세 구조로 인하여 재료비를 절약하면서 우수한 기계적 특성을 나타내는 플라스틱 재료를 성형할 수 있게 하며, 발포제로 초 임계 상태의 불활성 기체($CO_2$, $N_2$, etc)를 사용하기 때문에 기존의 발포 공정에서 발포제로 사용했던 유해 화학 물이나 프레온, 부탄으로 인해 발생할 수 있는 환경 문제를 해결할 수 있다는 장점을 지닌다.(중략)

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.77-77
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• 2004

현재 플라스틱 제품의 재료 절감을 통한 원가 절감과 아울러 기계적 성질을 더 향상시키거나 유지하기 위한 초미세 발포 공법이 주목받고 있다. 이론 위해 많은 연구가 진행되어 왔으나 아직까지도 셀의 미소화, 균일화 그리고 표면 품위 등을 위한 지속적인 연구가 요구되고 있다. 초미세 발포 사출에서 셀의 형상에 영향을 주는 인자는 여러 가지이다 우선 사출 속도에 영향을 받으며, 사출 온도에 따라서도 많은 영향을 받는다.(중략)

• 대한기계학회논문집A
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• 제29권5호
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• pp.655-662
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• 2005

This paper investigates the improvement of accuracy and fatigue life of the developed counter pressurized microcellular gears of polyacetal. It is shown that the fatigue life and operational characteristics of the counter pressurized microcellular gears are more improved than conventional injection molded plastic gears by the dynamic gear durability test. For the cases of test sea.5. conventional injection molded sea.5(SGea.) and counter pressurized microcellular gears(CGear) are manufactured. Durability test is performed on both conventional lnjection molded gears and counter pressurized microcellular gears. Accuracy variation and operational characteristics on fatigue life, wear and tooth surface temperature of CGear and Scear are compared and represented. Operational characteristics of the proposed counter pressurized microcellular gears show a good result in this research. The durability limit of counter pressurized microcellular gears is also obtained, and represented by a function of unit load as well as by a function off-factor.

• 한국정밀공학회지
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• 제22권12호
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• pp.87-92
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• 2005

In microcellular injection molding, gas supply system is needed. But, that device is very expensive to attach to the injection molding machines. So, new method is needed and gas-pellets MCPs is one of the solutions. In gas-pellets MCPs, there will be strange characteristics. In this paper, some characteristics are described on the view point of saturation pressure and saturation time.

• 한국정밀공학회지
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• 제25권9호
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• pp.71-77
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• 2008

Microcellular foaming plastics create a sensation at polymer industrial for lowering product costs and overcoming a lowering of mechanical intensity. Among many advantages, microcellular foaming plastics is well known to have a good acoustical properties. This research based on the experiment of sound absorption and transmission characteristics inquire into acoustical properties of microcellular foaming plastics. Difference of transmission loss of microcellular foaming plastics and solid materials was defined as cell effect. Also, cell effect is expressed by sound reflection and sound absorption. This study is expected to fundamental research to present economical, functional alternative plan for products using sound absorption and transmission materials.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.419-420
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• 2007

• 대한기계학회논문집A
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• 제29권5호
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• pp.647-654
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• 2005

This research Proposes a Process design of injection molded microcellular plastic gears for enhancing the fatigue strength/durability and accuracy of the gears applying thermodynamic instability to microcellular foaming process. To develop the injection molded plastic gears by way of microceliular process, it is absolutely necessary the following two process design. The first is microcellular forming process for enhancing the strength/durability of plastic gears. To be microcellular process succeeded, based on the microcellular principle, mechanical apparatus is designed where nucleation and cell growth are to be generated renewably. The second is the counter pressure process which is mainly fur improving the tooth surface roughness and the accuracy of microcellular gears. For the former process, screw, nozzle and gas equipment are newly designed, and for the latter, counter pressure by nitrogen gas is intentionally brought about into mold cavity when injecting plastic gears. Based on the proposed process design, using gear mold, experiments of injection molding show that, in internal space of plastic gears, microcellular nuclear cells less than 5 lim in diameter have been generated homogeneously via electron microscope photos.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.751-752
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• 2012

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 추계학술대회 논문집
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• pp.403-404
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• 2009

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.725-726
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• 2012