Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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High Strain Rate Compression Behavior of EPP Bumper Foams

변형률 속도에 따른 EPP Foam의 대변형 동적 압축 특성에 관한 연구

  • Choi, Ki-Sang (Structural Durability Research Center, Korea Automotive Technology Institute) ;
  • Kang, Woo-Jong (School of Mechanical & Automotive Engineering, Kyungil University) ;
  • Kim, Gi-Hoon (Structural Durability Research Center, Korea Automotive Technology Institute) ;
  • Kim, Seong-Kun (Department of Automotive Engineering, Hoseo University)
  • 최기상 (자동차부품연구원 내구기술연구센터) ;
  • 강우종 (경일대학교 기계자동차학부) ;
  • 김기훈 (자동차부품연구원 내구기술연구센터) ;
  • 김성근 (호서대학교 자동차공학과)
  • Received : 2008.12.15
  • Accepted : 2009.02.11
  • Published : 2009.07.01
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Abstract

Bumper is designed to protect the automotive frame without damage at low velocity. Expanded polypropylene (EPP) foam is used in the bumper as an energy absorbing material. In order to exactly predict the energy absorbing performance of the foam material under impact loading condition, it is important to use high strain rate material properties. In this study, a new apparatus for dynamic compression tests was developed to investigate the high strain rate behavior of EPP foams. Three kinds of EPP foams which have different expansion ratios were tested to investigate the quasi-static and dynamic compression behavior. Quasi-static compressions were performed at low strain rates of 0.001/s, 0.1/s and 1/s. The dynamic compressions were carried out at high strain rates of 50/s and 100/s with the developed apparatus. It was observed that the EPP foam has significant strain rate effect as compared to quasi-static behavior.

Keywords

References

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