Observations on Dynamic Strain Aging Manifestation in Inconel 718 Superalloy

Abstract:

The manifestation of dynamic strain aging (DSA) in Inconel 718 is reported in this work. Analysis were performed in the material with different microstructures resulting from solution anneal and aging treatment. Tensile tests were made under secondary vacuum with temperature ranging between 200 and 950°C and strain rates of 3.2 x 10^-3 to 3.2 x 10^-5 s^-1. Results showed the range of DSA occurrence. Analysis indicates that at lower temperatures, from approximately 200 to 450°C, serrations are controlled by the diffusion of carbon. At higher temperatures, until 800°C, DSA coincided with the occurrence of other thermally activated phenomena: dynamic precipitation, especially γ’’, and Oxidation Assisted Intergranular Cracking (OAIC). It was observed that competitive phenomena affect DSA manifestation directly due to the availability of niobium in solid solution.

• Periodical: Materials Science Forum (Volume 930)
• Pages: 390-394
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.930.390
• Online since: September 2018
• Authors: Monica Costa Rezende, Leonardo Sales Araújo, Sinara Gabriel Borborema, Jean Dille, Luiz Henrique de Almeida
• Keywords: Dynamic Strain Aging, Inconel 718, OAIC

References

[1] W. Chen, M.C. Chaturvedi: Materials Science and Engineering Vol. 229 (1997), p.163.

[2] S.A. Nalawade, M. Sundararaman, R. Kishore, J.G. Shah: Scripta Materialia Vol. 59 (9) (2008), p.991.

[3] M.L. Weaver, C.S. Hale: Effects of precipitation on serrated yielding in Inconel 718". Superalloys 718,625-706 and Various Derivatives, (2001) 421-432.

DOI: 10.7449/2001/superalloys_2001_421_432

[4] C.L. Hale, W.S. Rollings, M.L. Weaver: Materials Science and Engineering: A Vol. 300 (1) (2001), p.153.

[5] R.W. Hayes: Acta Metallurgica Vol. 31 (3) (1983), p.365.

[6] P. Maj, J. Zdunek, M. Gizynski, J. Mizera, K.J. Kurzydlowski: Mat. Sci. & Eng. A Vol. 619 (2014), p.158.

[7] V. Garat, et al.: Journal of Nuclear Materials Vol. 375 (2008), p.95.

[8] M.C. Rezende et al.: Journal of Alloys and Compounds Vol. 643 (2015), p. S25.

[9] L.H. Almeida, R.R.O. Emygdio: Scripta Metallurgica et Materialia Vol. 31 (1994), p.505.

[10] R.W. Hayes, W.C. Hayes: Acta Metallurgica Vol. 30 (1982), p.1295.

[11] 17 do Hale.

[12] W. Carpenter, B.S.J. Kang, K.M. Chang: Superalloys 718, 625, 706 and Various Derivatives (1997), p.679.

DOI: 10.7449/1997/superalloys_1997_679_688

[13] T. Connolley, M.J. Starink, P.A.S. Reed: TMS (2000), p.435.

[14] F. Delaunayrid et al.: Microchimica Acta Vol. 132 (2000), p.337.

[15] L. Fournier, D. Delafosse, T. Magnin: Materials Science and Engineering A Vol. 316 (2001), p.166.

[16] M. Gao, R.P. Wei: Scripta Materialia Vol. 37 (1997), p.1843.

[17] V. Garat, et al.: Superalloys Vol. 718 (2006), p.625.

[18] X.J. Pang et al.: Scripta Metallurgica et Materialia Vol. 31 (1994), p.345.