Advertisement

Effect of Nb on Microstructure and Mechanical Properties of High-Strength Low-Alloy Welding Layer

  • Tengyang Xiong
  • Bin Wang
  • Yiwen Hu
  • Jing Hu
  • Senfeng Zhang
Conference paper
Part of the Springer Proceedings in Energy book series (SPE)

Abstract

Using Q345 steel as a substrate, six kinds of high-strength low-alloy welding layers with different Nb contents were obtained by manual arc welding and chemical composition transition of electrode coating, and the effect of Nb on microstructure and properties of welding layers were investigated. The results showed that with the increase of Nb content, the microstructure was gradually uniform and the grains were obviously refined. The lath bainite in the welding layers gradually changed into granular bainite and when Nb content is 0.11%, the microstructure showed a whole granular bainite with no lath bainite. Furthermore, with Nb content increasing, NbC precipitates appeared on grain boundaries and decreased the grain size of M/A structure when the NbC precipitates increased. As Nb content varied from 0.0041 to 0.26 wt%, the yield strength increased from 560 to 751 MPa, and tensile strength increases from 630 to 815 MPa. The yield ratios are similar for both cases, while the elongation decrease slightly. At the temperature of −20 and −40 °C, the impact energy significantly increases from 30.2 and 13.0 J to 166.7 and 138.1 J, respectively. The hardness increases first, then decreases, and increases slowly again.

Keywords

Nb High-strength low-alloy welding layer NbC Microstructure Mechanical properties 

References

  1. 1.
    Y.Y. Ren, G.S. Zhang, S.Z. Wei et al., The development and prospect of China’s surfacing technology. J. Weld. Technol. 41, 1–4 (2012)Google Scholar
  2. 2.
    X.Y. Han, Functions of Nb, V and Ti in micro-alloyed steel. J. Wide Heavy Plate. 12, 39–41 (2006)Google Scholar
  3. 3.
    Z.Y. Dong, Q.Y. Huang, in Proceedings of the Eighth National Conference on welding. Development status of surfacing welding in China and abroad (Machinery Industry Press, Beijing, 1997)Google Scholar
  4. 4.
    T.F. Wei, L.J. Gan, Q.D. Wang, Effect of Nb on microstructure and properties of low carbon microalloyed steel. J. Therm. Process. Technol. 14, 126–128 (2015)Google Scholar
  5. 5.
    J.Y. Fu, Nb microalloying and niobium-containing steel development and technological progress. J. Iron Steel. 40, 1–6 (2005)Google Scholar
  6. 6.
    J.J. Qi et al., Micro-Alloyed Steels (Metallurgy Industry Press, Beijing, 2006)Google Scholar
  7. 7.
    Q.L. Yong, H.Z. Pei, J.G. Tian et al., Physical data of niobium in steel. J. Iron Steel Res. 10, 66–69 (1998)Google Scholar
  8. 8.
    S. Traint, A. Pichler, R. Sierlinger et al., Low-alloyed TRIP-steels with optimized strength, forming and welding properties. J. Steel Res. Int. 77, 641–649 (2006)CrossRefGoogle Scholar
  9. 9.
    H. Hu, G. Xu, L. Wang et al., The effects of Nb and Mo addition on transformation and properties in low carbon bainitic steels. J. Mater. Design. 84, 95–99 (2015)CrossRefGoogle Scholar
  10. 10.
    J.Y. Fu, F.M. Meng, Technology and development of Nb-containing steel for automobile industry. J. Automot. Process Mater. 6, 26–31 (2004)Google Scholar
  11. 11.
    K. Yang, Q. Yang, Y.F. Bao, Formation of carbonitride precipitates in hardfacing alloy with niobium addition. J. Rare Metals. 32, 52–56 (2013)CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Tengyang Xiong
    • 1
  • Bin Wang
    • 1
    • 2
  • Yiwen Hu
    • 1
  • Jing Hu
    • 1
  • Senfeng Zhang
    • 1
  1. 1.School of Materials Science and EngineeringSouthwest Petroleum UniversityChengduChina
  2. 2.Welding Engineering Technology Research CenterChengduChina

Personalised recommendations