Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A study on the thickness distribution and pattern deformation of films in vacuum-assisted thermoforming

열진공성형에서 발생하는 필름의 두께 분포와 패턴 변형에 관한 연구

  • Seong, Gyeom-Son (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation) ;
  • Lee, Ho-Sang (Dep. of Aeronautical & Mechanical Design Eng., Korea Nat'l Univ. of Transportation)
  • 성겸손 (한국교통대학교 항공기계설계학과) ;
  • 이호상 (한국교통대학교 항공기계설계학과)
  • Received : 2018.05.18
  • Accepted : 2018.08.01
  • Published : 2018.08.01
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Abstract

Vacuum-assisted thermoforming is one of the critical steps for successful application of film insert molding(FIM) to parts of complex shape. In this study, the simulations and experiments of thermoforming processes were performed to investigate the effects of process conditions on thickness distribution and printed pattern deformation of films in vacuum-assisted thermoforming. The film thickness uniformity increased with decreasing film heating time, whereas it increased with increasing vacuum delay time. After thermoforming of films with uniform pattern space of 5mm, the maximum space was 9.432mm. Based on the simulation, a modified pattern was calculated to obtain uniform spaces after thermoforming. In the experiments for film with the modified pattern, the maximum space appeared 5.837mm. In, addition. the predicted patterns were in good agreement with the experimental results.

Keywords

Acknowledgement

Supported by : 한국연구재단

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