Effect of long-term service on the precipitates in P92 steel

  • Yan-ping ZengEmail author
  • Jin-dou Jia
  • Wen-he Cai
  • Shu-qing Dong
  • Zhi-chun Wang


The precipitates in P92 steel after long-term service in an ultra-supercritical unit were investigated by field-emission scanning electron microscopy and transmission electron microscopy and were found to mainly consist of M23C6 carbides, Laves phase, and MX carbonitrides. No Z-phase was observed. M23C6 carbides and Laves phase were found not only on prior austenite grain boundaries, martensite lath boundaries, and subgrain boundaries but also in lath interiors, where two types of MX carbonitrides—Nb-rich and V-rich particles— were also observed but the “winged” complexes were hardly found. Each kind of precipitate within the martensite laths exhibited multifarious morphologies, suggesting that a morphological change of precipitates occurred during long-term service. The M23C6 carbides and Laves phase coarsened substantially, and the latter grew faster than the former. However, MX carbonitrides exhibited a relatively low coarsening rate. The effect of the evolution of the precipitate phases on the creep rupture strength of P92 steel was discussed.


precipitate P92 steel long-term service ultra supercritical unit 


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Copyright information

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

Authors and Affiliations

  • Yan-ping Zeng
    • 1
    Email author
  • Jin-dou Jia
    • 1
  • Wen-he Cai
    • 2
  • Shu-qing Dong
    • 2
  • Zhi-chun Wang
    • 2
  1. 1.School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingChina
  2. 2.North China Electric Power Research Institute Co., Ltd.BeijingChina

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