Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Effect of Chemical Composition on Tensile Property in TRIP-assisted Multiphase Steel for Automobile Structure

차량구조용 변태유기소성(TRIP)형 복합조직강의 인장성질에 미치는 화학조성의 영향

  • Lee, Ki-Yeol (Jeonnam Advanced Materials Industrialization Center) ;
  • Bang, Il-Hwan (Jeonnam Advanced Materials Industrialization Center) ;
  • Ma, Ah-Ram (Jeonnam Advanced Materials Industrialization Center) ;
  • Kim, Young-Sun (Jeonnam Advanced Materials Industrialization Center)
  • 이기열 ((재)전남테크노파크 신소재기술산업지원센터) ;
  • 방일환 ((재)전남테크노파크 신소재기술산업지원센터) ;
  • 마아람 ((재)전남테크노파크 신소재기술산업지원센터) ;
  • 김영순 ((재)전남테크노파크 신소재기술산업지원센터)
  • Published : 2007.05.01
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Abstract

The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types : a granular type in a steel containing higher sillicon and a film type in a steel having higher carbon. For the case of higher carbon-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable silicon and manganese, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher manganese content exhibited the assimilar behavior shown in dual phase steel.

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References

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