Microstructural Aspects of Low Cycle Fatigue of Aged GX12CrMoVNbN9-1 Cast Steel

Abstract:

The paper presents the results of research on the changes in microstructure of GX12CrMoVNbN9-1 cast steel subject to aging at the temperature of 600°C and holding time of 8000 hours, followed by low-cycle fatigue. The characteristics of the microstructure of the examined cast steel after ageing and low-cycle fatigue was described using transmission electron microscopy (study of the dislocation microstructure) and morphology of precipitations. It has been shown that low cycle fatigue leads to the matrix softening as a result of the processes of recovery, polygonization and repolygonization. Moreover, the processes of precipitation of Laves phase and coagulation of M₂₃C₆ carbides were observed in the microstructure. Intensity of these processes depended not only on the temperature of fatigue tests, but also on the level of total strain amplitude ε_ac.

• Periodical: Key Engineering Materials (Volumes 592-593)
• Pages: 708-711
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.592-593.708
• Online since: November 2013
• Authors: Stanisław Mroziński, Grzegorz Golański, Krzysztof Werner
• Keywords: Aging, Cast Steel, Low Cycle Fatigue, Microstructure

References

[1] Li Qiang: Mater. Sc. Eng., A361 (2003), p.385.

[2] A. Zieliński, J. Dobrzański and M. Soroka: Arch. Mater. Sc. Eng., 49/2 (2011), p.103.

[3] R. Viswanathan: Damage mechanisms and life assessment of high temperature components, ASM International, Metals Park Ohio, USA, (1989).

[4] G. Golański: Materials Science, 48 3 (2012), p.384.

[5] F. A. Schuster, R. Hanus and H. Cerjak, Proc. I. Mech. Eng., (1996), p.11.

[6] S. Mroziński and G. Golański: Inter. J of Eng. and Tech., 13 1 (2013), p.86.

[7] D. Rozumek, E. Macha: Mater. Sci., 45(2) (2009), p.190.

[8] G. Golański and J. Kępa, Arch. Metall. and Mater., 57 2 (2012), p.575.