Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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A Study on The Change of Birefringence Structure in Injection and Injection/compression Molded Products

사출 및 사출/압축 성형품 내에서의 복굴절 구조 변화에 관한 연구

  • 민인기 (단국대학교 대학원 기계공학과) ;
  • 이경범 (단국대학교 대학원 기계공학과) ;
  • 윤경환 (단국대학교 대학원 기계공학과)
  • Received : 2010.03.25
  • Accepted : 2010.07.16
  • Published : 2010.08.01
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Abstract

It is still needed to study the effect of process conditions on the final properties of injection-molded parts for producing precision optical products. Especially, the optical anisotropy, i.e., birefringence, is a significant factor to affect the function of many optical components. In the present study we have focused on the effect of holding and compression processes on the birefringence remaining in the transparent disc by examining the gap-wise distribution of birefringence and extinction angle. As a result, two extra birefringence and extinction peaks near the center in thickness direction showed the effect of holding pressure, which came from the flow in packing stage. However, more uniform birefringence distribution than injection-only cases could be found in injection/compression cases. Depends on the process condition even the flow reversal could be found from the distribution of extinction angle. Finally, graphical representation of optical indicatrix was added for better understanding the final structure of injection-only and injection/compression cases.

Keywords

References

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