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Effect of Original Microstructure on the Hot Compression Behavior of Superalloy 718

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Abstract:

Hot compression tests at different temperatures and strain rates were performed on superalloy 718 annealed at 1100 °C for 30 min as well as 950 °C for 30 min in order to investigate the effect of the original microstructure on the hot deformation behavior. The results show that the δ phase precipitated on the grain boundaries of superalloy 718 prior to hot deformation leads to a decrease of the flow stress, which can be attributed to the drop of the matrix strength. The activation energy (Q) for hot deformation of the fine-grained material with δ phase on the grain boundaries is determined to be 381 kJ/mol, which is much lower than that of the coarse-grained material without δ phase (472 kJ/mol). It is suggested that the initial δ phase precipitated on the grain boundaries of the annealed material affect the thermal activation process of hot deformation for superalloy 718, resulting in the decrease of activation energy.

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Periodical:

Key Engineering Materials (Volumes 353-358)

Pages:

515-518

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.353-358.515

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Online since:

September 2007

Authors:

Y. Wang, Wen Zhu Shao, Liang Zhen, L. Lin, Xin Mei Zhang

Keywords:

Activation Energy, Flow Stress, Original Microstructure, Superalloy 718, δ Phase

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© 2007 Trans Tech Publications Ltd. All Rights Reserved

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References

[1] R. Srinivasan, V. Ramnarayan and U. Deshpande: Met. Trans Vol. 24A (1993), p. (2061).

Google Scholar

[2] C.I. Garcia, G.D. Wang and D.E. Camus, in: E.A. Loria (Ed. ), Superalloys 718, 625, 706 and Various Derivatives, TMS, Warrendale, PA (1994), p.293.

DOI: 10.7449/1994/superalloys_1994_293_302

Google Scholar

[3] J.M. Zhang, Z.Y. Gao and J.Y. Zhuang: Met. Mater. Trans Vol. 30A (1999), p.2701.

Google Scholar

[4] S.C. Medeiros, Y.V.R.K. Prasad and W.G. Frazier: Scripta. Mater Vol. 42 (2000), p.17.

Google Scholar

[5] H. Yuan, W.C. Liu: Mater. Sci. Eng Vol. A408 (2005), p.281.

Google Scholar

[6] W. Dix, J. M. Hyzak and R. P. Singh, in: E.A. Loria (Ed. ), Superalloys, TMS, Warrendale, PA (1992), p.23.

Google Scholar

[7] W. Chen, M.C. Chaturvedi: Mater. Sci. Eng Vol. A183 (1997), p.81.

Google Scholar

[8] C. M. Sellars, W. J. Tegart: Membr. Sci. Rev. Met Vol. 63 (1966), p.731.

Google Scholar