# 차체용 강판의 온도에 따른 동적 구성방정식에 관한 연구 (I) - 온도에 따른 동적 물성 특성 -

• 이희종 (한국과학기술원 기계공학과) ;
• 송정한 (한국과학기술원 기계공학과) ;
• 박성호 (포스코 자동차강재연구센터) ;
• 허훈 (한국과학기술원 기계공학과)
• Published : 2007.02.01

#### Abstract

This paper is concerned with the thermo-mechanical behavior of steel sheet for an auto-body including temperature dependent strain rate sensitivity. In order to identify the temperature-dependent strain rate sensitivity of SPRC35R, SPRC45E and TRIP60, uniaxial tensile tests are performed with the variation of the strain rates from 0.001/sec to 200/sec and the variation of environmental temperatures from $-40^{\circ}C$ to $200^{\circ}C$. The thermo-mechanical response at the quasi-static state is obtained from the static tensile test and that at the intermediate strain rate is obtained from the high speed tensile test. Experimental results show that the variation of the flow stress and fracture elongation becomes sensitive to the temperature as the strain rate increases. It is observed that the dynamic strain aging occurs with TRIP60 at the temperature above $150^{\circ}C$. Results also indicate that the flow stress and tincture elongation of SPRC35R are more dependent on the changes of strain rates and temperature than those of SPRC45E and TRIP60.

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#### Cited by

1. Reliability Assessment of Impact Tensile Testing Apparatus using a Drop-bar Striker for Intermediate Strain-rate Range and Evaluation of Dynamic Deformation Behaviors for a Carbon Steel vol.40, pp.6, 2016, https://doi.org/10.3795/KSME-A.2016.40.6.573