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China Foundry

, Volume 16, Issue 1, pp 23–30 | Cite as

Directional solidification casting technology of heavy-duty gas turbine blade with liquid metal cooling (LMC) process

  • Xiao-fu LiuEmail author
  • Yan-chun Lou
  • Bo Yu
  • Gui-qiao Su
  • Chang-chun Li
  • Xin-li Guo
  • Biao Li
  • Guo-yan Shui
Research & Development
  • 10 Downloads

Abstract

In this work, some important factors such as ceramic shell strength, heat preservation temperature, standing time and withdrawal rate, which influence the formability of directionally solidified large-size blades of heavy-duty gas turbine with the liquid metal cooling (LMC) process, were studied through the method of microstructure analysis combining. The results show that the ceramic shell with medium strength (the high temperature flexural strength is 8 MPa, the flexural strength after thermal shock resistance is 12 MPa and the residual flexural strength is 20 MPa) can prevent the rupture and runout of the blade. The appropriate temperature (1,520 °C for upper region and 1,500 °C for lower region) of the heating furnace can eliminate the wide-angle grain boundary, the deviation of grain and the run-out caused by the shell crack. The holding time after pouring (3-5 min) can promote the growth of competitive grains and avoid a great deviation of columnar grains along the crystal orientation <001>, resulting in a straight and uniform grain structure. In addition, to avoid the formation of wrinkles and to ensure a smooth blade surface, the withdrawal rate should be no greater than the growth rate of grain. It is also found that the dendritic space of the blade decreases with the rise of solidification rate, and increases with the enlarging distance between the solidification position and the chill plate.

Key words

liquid metal cooling (LMC) heavy-duty gas turbine large-size blade directional solidification microstructure 

CLC numbers

TG132.3+

Document code

References

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Copyright information

© Foundry Journal Agency and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Xiao-fu Liu
    • 1
    Email author
  • Yan-chun Lou
    • 1
  • Bo Yu
    • 1
  • Gui-qiao Su
    • 1
  • Chang-chun Li
    • 1
  • Xin-li Guo
    • 1
  • Biao Li
    • 1
  • Guo-yan Shui
    • 1
  1. 1.State Key Laboratory of Light Alloy Casting Technology for High-end EquipmentShenyang Research Institute of Foundry Co., Ltd.ShenyangChina

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