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Microstructure and Properties of a Low Carbon Ti-V Microalloyed Steel

  • Xinhua Pei (裴新华)
  • Zhenyu Liu
  • Jiao Wei
  • Xuefeng Liu
  • Tao Jia (贾涛)Email author
  • Hengfa Hu
Metallic Materials
  • 6 Downloads

Abstract

Due to the largely inhomogeneous deformation among constituent phases, the advanced high-strength multi-phase steels are always facing challenges when applied to automotive parts where local formability is critically required. In this work, two characteristic microstructures were produced from a low carbon Ti-V microalloyed steel by varying the cooling path. In the ferrite single-phase microstructure resulted from “ultra-fast cooling (UFC) + furnace-cooling (FC)”, the hole-expanding ratio of 200% and tensile strength of 647 MPa were achieved. In the ferrite-bainite-martensite (F+B+M) multi-phase microstructure produced by “UFC + air-cooling (AC) + UFC”, the ferrite has been strengthened by Ti-V carbides to promote the strain partitioning, which resulted in the tensile strength of ≥780MPa, a moderate elongation and hole-expanding ratio of 93%. The strengthening contributions of Ti-V carbides were calculated to be 126MPa and 149MPa in the ferrite single-phase and F+B+M multi-phase microstructure, respectively.

Key words

orowan strengthening ultra-fast cooling high-strength hole-expanding ratio Ti-V carbide 

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Copyright information

© Wuhan University of Technology and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Xinhua Pei (裴新华)
    • 1
    • 2
  • Zhenyu Liu
    • 1
  • Jiao Wei
    • 3
  • Xuefeng Liu
    • 1
  • Tao Jia (贾涛)
    • 1
    Email author
  • Hengfa Hu
    • 2
  1. 1.The State Key Lab of Rolling & AutomationNortheastern UniversityShenyangChina
  2. 2.Meishan Iron & Steel Co., LtdNanjingChina
  3. 3.BaoSteel Co., LtdShanghaiChina

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