Deformation Twinning Behavior in High Ni-Austenitic Materials

Abstract:

Deformation twinning behaviors have been studied in high Ni alloys, Alloy 28 or Sanicro 28 and Alloy 625 at RT and at cryogenic temperature. The microstructures were evaluated using SEM-EBSD. Some constitutive approach has also been used in the discussion on the deformation twinning in high Ni-alloys. The results show that deformation twinning can occur in high Ni alloys depending on the chemical composition, strain range and stress conditions. TWIP can occur in the Ni based superalloy Alloy 625 at cryogenic temperature, which increases both strength and ductility. This is the first report of this phenomena for this alloy. Deformation twinning in high Ni alloys occurs heterogeneously in the material, depending on crystallographic parameters such as grain orientation and Schmid factor. Formation of deformation twins can lead to high texture in the material, which will contribute to the increase of strength. The mechanisms for the formation of deformation twins in high Ni alloys have been discussed.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 1591-1596
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.1591
• Online since: December 2018
• Authors: Joakim Nordström, Raveendra Siriki, Johan Moverare, Guo Cai Chai*
• Keywords: Ageing, Fracture Toughness, Microstructure, Nickel Based Superalloy, Twinning

References

[1] B.C. De Cooman, Y. Estrin, and S.K. Kim, Twinning-induced plasticity (TWIP) steels, Acta Materialia, 2018. 142: pp.283-362.

DOI: 10.1016/j.actamat.2017.06.046

[2] B. Geddes, H. Leon and X. Huang, Superalloys: Alloying and Performance, ASM International, 2010, ISBN-13: 978-1-61503-040-8.

[3] J.W. Christian and S. Mahajan, Deformation twinning, Progress in Materials Science, 1995. 39(1): pp.1-157.

[4] B.A. Bilby and A.G. Crocker, The Theory of the Crystallography of Deformation Twinning, Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1965. 288(1413): pp.240-255.

DOI: 10.1098/rspa.1965.0216

[5] B. C. De Cooman, O. Kwon and K-G. Chin, State-of-the-knowledge on TWIP steel, Materials Science and Technology, 2012: VOL 28: NO 5:513:527.

DOI: 10.1179/1743284711y.0000000095

[6] O. Grassel, L. Kruger, G. Frommeyer and L. Meyer, Int. J. Plast., 2000, 16, 1391.

[7] S.L. Shang, et al., Effects of alloying element and temperature on the stacking fault energies of dilute Ni-base superalloys, Journal of Physics Condensed Matter, 2012, 24(50).

DOI: 10.1088/0953-8984/24/50/505403

[8] L. L. Shawa, J. Villegas, J-Y. Huangb, S. Chenc. Strengthening via deformation twinning in a nickel alloy, Materials Science and Engineering, 2008, A 480 75–83.

DOI: 10.1016/j.msea.2007.06.072

[9] M. A. Meyers, O. Vohringer, and V. A. Lubarda, The onset of twinning in metals: a constitutive description, Acta mater, 2001, 49 4025–4039.

DOI: 10.1016/s1359-6454(01)00300-7

[10] ASM Metals Handbook, 10th ed., 1990, ASM INTERNATIONAL, Materials Park, OH.