A Study on the Prediction of Grain Size Distribution in Hot Forging of Waspaloy Turbine Disc

Waspaloy 터빈디스크의 열간 단조시 결정립분포 해석에 관한 연구

  • 염종택 (한국기계연구소 재료기술연구소, 포항공과대학교 신소재공학과) ;
  • 이종수 (포항공과대학교 신소재공학과) ;
  • 김정한 (한국기계연구소 재료기술연구소) ;
  • 이동근 (한국기계연구소 재료기술연구소) ;
  • 박노광 (한국기계연구소 재료기술연구소)
  • Published : 2006.06.01

Abstract

The microstructure evolution during a hot forging of Waspaloy was investigated using the recrystallization model and FEM simulation. In order to obtain an uniform microstructure, hot forging was carried out by two step. The change of grain size during hot forging has a deep connection with dynamic recrystallization behavior. Avrami-type constitutive equation for the dynamic recrystallization was implemented into an user subroutine of 2D FE simulator. The evolution of grain structure in the two-step forging of Waspaloy was simulated using the 2D FEM user-subroutine. The detailed variation of microstructures due to dynamic recrystallization could effectively be predicted at various locations in a forged pancake.

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References

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