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Transformation behavior of low carbon steels containing two different Si contents

  • Ming-hui Cai
  • Hua Ding
  • Jian-su Zhang
  • Long Li
  • Xiao-bin Li
  • Lin-xiu Du
Article

Abstract

Continuous cooling transformation behaviors of low carbon steels with two Si contents (0. 50% and 1. 35%) were investigated under undeformed and deformed conditions. Effects of Si contents, deformation, and cooling rates on y transformation start temperature (Ar3 ), phase microstructures, and hardness were studied. The results show that, in the case of the deformation with the true strain of 0. 4, the length of bainitic ferrite laths is significantly decreased in low Si steel, whereas, the M/A constituent becomes more uniform in high Si steel. An increase in cooling rates lowers the Ar3 greatly. The steel with higher level of Si exhibits higher Ar3, and higher hardness both under undeformed and deformed conditions compared with the steel with a lower Si content. Especially, the influence of Si on Ar3 is dependent on deformation. Such effects are more significant under the undeformed condition. The hardness of both steels increases with the increase of cooling rates, whereas, the deformation involved in both steels reduces the hardness.

Key words

Si content low carbon steel cooling rate transformation behavior bainitic morphology 

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Copyright information

© China Iron and Steel Research Institute Group 2009

Authors and Affiliations

  • Ming-hui Cai
    • 1
  • Hua Ding
    • 1
    • 2
  • Jian-su Zhang
    • 3
  • Long Li
    • 4
  • Xiao-bin Li
    • 1
  • Lin-xiu Du
    • 2
  1. 1.College of Materials and MetallurgyNortheastern UniversityShenyang, LiaoningChina
  2. 2.State Key Laboratory of Rolling AutomationNortheastern UniversityShenyang, LiaoningChina
  3. 3.Technology CenterBaoshan Iron and Steel Group CoShanghaiChina
  4. 4.National Institute for Materials ScienceTsukubaJapan

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