Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Study on the Development of 340MPa Grade Super Formable High Strength Steel Sheets

340MPa 급 초고성형성 고강도강판 개발에 관한 연구

  • Kim, Yong-Hee (School of Advanced Materials Engineering & RCAMD, Chonbuk National University) ;
  • Lee, Young-Soo (Technical Research Center, Hyundai HYSCO) ;
  • Lee, Oh-Yeon (School of Advanced Materials Engineering & RCAMD, Chonbuk National University)
  • 김용희 (전북대학교 신소재공학부, 신소재개발 연구센터) ;
  • 이영수 (현대하이스코 기술연구소) ;
  • 이오연 (전북대학교 신소재공학부, 신소재개발 연구센터)
  • Received : 2008.10.08
  • Accepted : 2008.02.10
  • Published : 2009.07.01
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Abstract

The demand for formable high-strength steel (HSS) sheets has recently increased to reduce the weight of automotive bodies. The 340MPa (Tensile Strength) grade steel sheets are widely used for body inner and outer panels. Especially, super formable 340MPa grade steel sheets with high r-value have an excellent deep drawability compared with the other 340MPa grade steel sheets. It is very available for a part such as rear floor, center floor and dash panels used conventional mild steels up to now. We developed a super formable HSS by optimization of chemical composition, texture control and heat treatment control. It has good mechanical properties with excellent formability (tensile strength: 343MPa, elongation: 41.1% and $\bar{r}=2.1$).

Keywords

References

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