• 제목/요약/키워드: Hot Radial Forging

검색결과 2건 처리시간 0.019초

Ni계 초내열합금 NIMONIC 80A의 고온변형거동 (High Temperature Deformation Behavior of a NIMONIC 80A Ni-based Superalloy)

  • 하민철;황시우;김종수;김철유;박경태
    • 소성∙가공
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    • 제22권5호
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    • pp.258-263
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    • 2013
  • The deformation behavior of NIMONIC 80A was studied in the high temperature range of $900{\sim}1200^{\circ}C$ and for strain rates varying between 0.02 and $20s^{-1}$ via the hot compression test. Processing maps for hot working were constructed on the basis of the power dissipation efficiency using a dynamic material model. The results showed that the strength during hot compression increased with increasing strain rate and decreasing temperature. At low strains, the processing map of NIMONIC 80A did not reveal any instability domain regardless of the strain rate and temperature. However, at high strains, the processing map exhibited an instability domain at a low strain rate of $0.2s^{-1}$ and within a temperature range of $900{\sim}960^{\circ}C$. In the instability domain, the deformed microstructure exhibited shear bands and carbide precipitation while, in the safe domain, full recrystallization occurred.