Elastomers and Composites

  • 제48권4호
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  • Pages.300-305
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  • 2013
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  • 2092-9676(pISSN)
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  • 2288-7725(eISSN)
한국고무학회 (The Rubber Society of Korea)
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DOI QR코드

DOI QR Code

유리섬유 강화 폴리카보네이트의 환상형상부품 사출성형시 성형수축에 관한 연구

A Study on the Part Shrinkage in Injection Molded Annular Shaped Product for Glass Reinforced Polycarbonate

  • 이민아 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 류민영 (서울과학기술대학교 기계시스템디자인공학과)
  • Lee, Mina (Dept. of Mechanical System Design Engineering, Seoul National Univ. of Science & Technology) ;
  • Lyu, Min-Young (Dept. of Mechanical System Design Engineering, Seoul National Univ. of Science & Technology)
  • 투고 : 2013.10.29
  • 심사 : 2013.11.06
  • 발행 : 2013.12.31
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초록

사출성형에서 성형수축은 피할 수 없는 현상이다. 따라서 성형수축을 줄이기 위한 연구가 필요할 뿐만 아니라 성형수축의 특성을 명확히 파악하는 것이 필요하다. 본 연구에서는 유리섬유로 보강된 폴리카보네이트를 이용하여 2.5차원형상인 환상형상의 시편에서 보이는 성형수축 현상을 조사하였다. 환상시편은 외경의 크기와 두께를 달리하여 설계하였다. 성형조건은 수지온도, 보압시간 및 보압크기를 변수로 설정하였다. 여러 성형조건으로 성형된 시편에서 내경과 외경의 크기가 변하는 양상에 대해서 분석하였다. 성형된 시편의 외경과 내경의 치수는 금형의 치수보다 작게 나타났다. 시편의 외경이 클수록, 그리고 시편의 두께가 두꺼울수록 수출율은 작게 나타났다. 또한 게이트의 위치에 따라 수축의 크기가 방향성을 보였다. 따라서 성형된 시편은 원형이 아니라 타원형으로 나타났고 게이트 방향으로 내경과 외경이 가장 큰 수축을 보였다. 수축된 제품의 형상조절을 위해서는 게이트 설계와 같은 금형설계가 중요하다고 판단된다.

Part shrinkage in injection molding is inevitable phenomenon. Thus, it is necessary not only study on the reducing part shrinkage but characterization of part shrinkage. In this study, part shrinkage in injection molded 2.5 dimensional annular shaped specimens has been studied using glass fiber reinforced PC. Annular shaped specimens were designed with various sizes of outer diameter and thickness. Injection temperature, packing time and packing pressure were selected for operational conditions. Profile variations of outer and inner diameters of molded specimens for various operational conditions were investigated. Sizes of outer and inner diameters of injection molded specimens were smaller than the sizes of mold. Part shrinkage decreased as outer diameter and thickness increased. Part shrinkage showed anisotropic behavior and it depended upon gate location. Subsequently, molded specimens were not circular but oval in shape, and showed the largest shrinkage in the direction of gate. It was realized that the mold design such as gate design is important to control the shape of molded products.

키워드

참고문헌

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피인용 문헌

  1. Prediction of Mechanical Property of Glass Fiber Reinforced Polycarbonate and Evaluation of Warpage through Injection Molding vol.38, pp.6, 2014, https://doi.org/10.7317/pk.2014.38.6.708
  2. Research trends in polymer materials for use in lightweight vehicles vol.16, pp.1, 2015, https://doi.org/10.1007/s12541-015-0029-x