Effect of LMC Processing Parameters on Casting Defects in Large-Scale Single Crystal IGT Blades

  • Wenjin Wu
  • Jingyang Chen
  • Qing Li
  • Lin Liu
  • Lamei Cao
  • Xin Tang
  • Chengbo Xiao
Conference paper

Abstract

The effects of liquid metal cooling (LMC) processing parameters including mold shell temperature, withdrawal rate and metal pouring temperature on casting defects of large-scale single crystal blades were investigated by orthogonal experiments. The results of range analysis showed that with the withdrawal rate increasing from 5 to 8 mm/min, primary dendrite arm spacing (PDAS) and secondary dendrite arm spacing (SDAS) were refined obviously. But the number of casting defects especially stray grains (SG) in transition region and helical section increased, because the solid-liquid interface became more concave. With the pouring temperature increasing from 1550 to 1570 °C, the number of casting defects increased. Dendrite structure was refined slightly and the solid-liquid interface became less concave with the mold shell temperature increased from 1540 to 1560 °C. Finally, the suggestions were proposed to optimize the LMC processing parameters and control casting defects formed during directional solidification.

Keywords

Liquid metal cooling Processing parameter Large-scale single crystal blade Casting defect 

Notes

Acknowledgements

The authors are grateful to the financial support provided by National Key R&D Program of China (No. 2016YFB0701402), National Natural Science Foundation of China (No. 51631008, 51331005 and 51690163) and Aeronautical Science Foundation of China (No. 2015ZE21006).

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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Wenjin Wu
    • 1
    • 2
  • Jingyang Chen
    • 2
    • 1
  • Qing Li
    • 2
  • Lin Liu
    • 1
  • Lamei Cao
    • 2
  • Xin Tang
    • 2
  • Chengbo Xiao
    • 2
  1. 1.State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi’anChina
  2. 2.Science and Technology on Advanced High Temperature Structural Materials LaboratoryBeijing Institute of Aeronautical MaterialsBeijingChina

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