Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Prediction of Residual Stress Caused by IML Process and Deformation Due to Thermal Impact

IML 성형과정에 따른 잔류응력 및 열 충격에 의한 변형 예측

  • Lee, Jae-Won (Dept. of Mechanical Engineering, Hongik Univ.) ;
  • Jang, Eu-Gene (Dept. of Mechanical and System Engineering, Hongik Univ.) ;
  • Shin, Seung-Won (Dept. of Mechanical and System Engineering, Hongik Univ.) ;
  • Park, Seung-Ho (Dept. of Mechanical and System Engineering, Hongik Univ.) ;
  • Chung, Ha-Seung (Dept. of Mechanical and System Engineering, Hongik Univ.)
  • 이재원 (홍익대학교 기계공학과) ;
  • 장유진 (홍익대학교 기계시스템디자인공학과) ;
  • 신승원 (홍익대학교 기계시스템디자인공학과) ;
  • 박승호 (홍익대학교 기계시스템디자인공학과) ;
  • 정하승 (홍익대학교 기계시스템디자인공학과)
  • Published : 2010.03.01
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Abstract

In this study, we developed a method to predict the residual stress distribution and thermal deformation caused by in-mold labeling (IML) processes. IML is one of the injection molding processes for injecting a material into a cavity and subsequently inserting a decorated film. The IML process can yield products with decorations of outstanding excellent quality in only one working step. Although the IML process has various advantages, it causes defects such as film delamination, wash-out, and flow marks. In particular, deformation is considered to be a major concern in terms of delamination. To validate the model, the deformation predicted by using a numerical model was compared with experimental results, and both results showed good agreement. We verified that the developed method can be used to obtain the design guidelines for preventing delamination in the initial design stage of the IML process.

본 논문에서는 In-Mold Labeling(IML) 공정을 이용한 제품생산 과정에서 발생하는 잔류응력과 열변형을 예측할 수 있는 해석모델을 개발하였다. IML 은 선 공정된 필름을 금형에 넣은 후 수지를 사출하여 제품을 생산하는 방법으로, 일반적인 사출성형 공정방법에 비해 뛰어난 색감을 구현할 수 있을뿐 아니라, 반영구적 보존 등의 다양한 장점을 얻을 수 있다. 반면, IML 공정을 이용한 제품 생산의 경우 필름박리 등의 다양한 불량 현상이 발생하기도 하는데, 이 중 필름박리 현상의 주요한 원인 중 한가지로 지목되는 열 변형 현상을 수치해석을 통해 예측하고, 실제 실험결과와 비교하여 연구의 신뢰성을 검증하였다. 이는 IML 공정을 통해 생산되는 제품의 초기설계 단계로부터 필름박리 및 열 변형을 예측하는데 활용될 수 있을 것으로 기대된다.

Keywords

References

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