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

The Korean Society of Mechanical Engineers (대한기계학회)
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Effects of Molding Condition on Surface Unevenness of GFRP Composites in Compression Molding

GFRP 복합재료의 압축성형에서 표면요철에 미치는 성형조건의 영향

  • Kim, Hyoung-Seok (Dept. of Advanced Parts and Materials Engineering, Chosun Univ. Graduate School) ;
  • Kim, Jin-Woo (Center for NDE, Iowa State Univ.) ;
  • Kim, Yong-Jae (Dept. of Electrical Engineering, Chosun Univ.) ;
  • Lee, Dong-Gi (Dept. of Mechatronics Engineering, Chosun Univ.)
  • Received : 2010.05.14
  • Accepted : 2010.08.16
  • Published : 2010.11.01
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Abstract

We have investigated the unexpected phenomena on the surface of molded GFRP composites. The major cause of the unevenness, as a result of which the surface becomes rough, is a shrinking of the matrix in the process of holding pressure and cooling temperature. The higher holding pressure load in a molding process and the lower demolding temperature in an annealing experiment, the better GFRP composites moldings improved its appearance. In addition, by taking the holding pressure and demolding temperature into consideration, we evaluate the process that causes the surface unevenness and the variation in the fiber projection height.

성형조건에 따른 GFRP 복합재료를 관찰하여, 성형품 표면의 불량원인을 조사했다. 표면거칠기에 영향을 주는 요철의 가장 주요한 발생원인은 보압 냉각 과정에서 발생하는 모재의 수축이었다. GFRP 복합재료 성형품 표면은 성형 시의 보압하중이 높을수록 좋아졌고, 서냉실험에서는 탈형온도가 낮을수록 성형품의 표면이 좋아졌다. 그리고 보압하중과 탈형온도를 고려하여, 성형품의 표면요철 생성과정과 섬유돌출 높이 변화를 규명했다.

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References

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