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A Study on the Strain-Rate Sensitivity According to the Temperature for Steel Sheets of an Auto-Body

차체용 강판의 온도에 따른 변형률속도 민감도 연구

  • 이희종 (한국과학기술원 기계공학과) ;
  • 송정한 (한국과학기술원 기계공학과) ;
  • 조상순 (한국과학기술원 기계공학과) ;
  • 박성호 (POSCO 기술연구소) ;
  • 허훈 (한국과학기술원 기계공학과)
  • Published : 2006.03.01

Abstract

This paper is concerned with the thermo-mechanical behavior including temperature dependent strain-rate sensitivity of steel sheet for an auto-body. In order to identify the temperature dependent strain-rate sensitivity of SPRC35R and SPRC45E, uniaxial tension tests are performed with the variation of the strain-rates from 0.001 /sec to 200 /sec at environmental temperatures varied from $-40^{\circ}C\;to\;200^{\circ}C$. The thermo-mechanical response at the quasi-static state is obtained with the static tensile test and at the intermediate strain-rate is from the high speed tensile test. Experimental results show that the strain-rate sensitivity increases at low temperature. It represents that as the strain-rate increases, the variation of flow stress becomes sensitive on the temperature. The results indicate that the flow stress of SPRC35R is more dependent on the changes of strain-rate and temperature than those of SPRC45E.

Keywords

References

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