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China Foundry

, Volume 16, Issue 2, pp 110–117 | Cite as

Dendritic branching patterns in platforms of complex Ni-based single crystal castings

  • Min Huang
  • Gong Zhang
  • Dong Wang
  • Zhi-cheng Ge
  • Yu-zhang Lu
  • Xiang-wei Jiang
  • Lang-hong Lou
Research & Development
  • 24 Downloads

Abstract

Dendritic branching patterns at variable cross-sections in Ni-based single crystal (SX) castings of different generations were investigated using optical microscope (OM), electro probe microanalyzer (EPMA), differential scanning calorimeter (DSC), Thermo-Cal software and Pro-CAST software. Results show that the dendritic branching patterns are similar in outward platform in SXs of different generations. That is, the primary dendrites (PDs) are introduced into the platform by developing a series of secondary dendrites (SDs) to occupy the bottom of the platform, and the ternary dendrites (TDs) originating from these SDs grow upward to fill up the platform. With the SX generation increasing, the undercooling of melts in the inward platform increases significantly due to the increasing alloying elements and the segregation in the directional solidification (DS) process, and the growth velocity of the dendrite tip increases according to the dynamic model of dendrite growth, which is beneficial for the high-order dendrite development. The stronger dendritic branching ability is shown in the inward platform of the higher generation Ni-based SX.

Key words

dendritic branching patterns platform undercooling 

CLC numbers

TG146.1+

Document code

Notes

Acknowledgements

This work was financially supported by the National Key Research and Development Program of China (No. 2017YFB0702904) and the National Natural Science Foundation of China (No. 51631008).

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Copyright information

© Foundry Journal Agency and Springer Singapore 2019

Authors and Affiliations

  • Min Huang
    • 1
    • 2
  • Gong Zhang
    • 1
  • Dong Wang
    • 1
  • Zhi-cheng Ge
    • 1
  • Yu-zhang Lu
    • 1
  • Xiang-wei Jiang
    • 1
  • Lang-hong Lou
    • 1
  1. 1.Institute of Metal ResearchChinese Academy of SciencesShenyangChina
  2. 2.University of Chinese Academy of SciencesBeijingChina

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