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Vol.5 , No. 2, Publication Date: Feb. 27, 2018, Page: 24-29
| [1] | Shamanth V., Department of Mechanical Engineering, SVCE, Bengaluru, Karnataka, India. |
| [2] | Ravishankar K. S., Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal, India. |
It is well known that the mechanical properties of austenitic-ferritic duplex stainless steels are strongly affected when they are subjected to the service temperature around 250°C to 500°C. This is because of the attribution of the spinodal decomposition of Fe-Cr solid solution within the ferritic matrix. Hence the use of duplex steels is limited to service temperatures below 250°C However the microstructural changes associated with the thermal aging can be reverted to the annealed condition by short term reversion heat treatment. In this investigation the effect of heat treatment on the mechanical properties of the thermally embrittled duplex steels has been studied. The aged and re-aged samples showed a significant increase in the tensile strength with respect to the annealed condition because of the spinodal decomposition in the ferritic phase. The effect of reversion heat treatment time was also studied in this investigation. Embrittled samples which were then reversion heat treated for 550°C for 60 minutes showed maximum recovery of 92% in the mechanical properties. As reversion heat treatment time was increased the recovery induced was decreasing because of the formation of secondary austenite and R-phase. Then 60minutes reversion heat treated samples were re-aged at 475°C for varying period’s in order to check the embrittlement rate and also to check the applicability and the effectiveness of the reversion heat treatment. The results showed that there was no much difference at the rate at which re-embrittlement occurs.
Keywords
Duplex Stainless Steels, Heat Treatment, Aging, Precipitates and Mechanical Properties
Reference
| [01] | M. Rosso, I. Peter, D. Suani, About heat treatment and properties of Duplex Stainless Steels, J. Ach. Mat. Manfg. Eng., 59 (1) (2013), pp. 26-36. |
| [02] | L. A. Dobrzanski, Z. Brytan, M. A. Grande, M. Rosso, “Properties of duplex stainless steels made by powder metallurgy”, Arch. Mater. Sci. Eng., 28 (4) (2007), pp 217-223. |
| [03] | Robert N. Gunn (Ed), “Duplex Stainless Steels, Microstructure, properties and applications”, Abington Publishing, 1997. |
| [04] | Mats Liljas, Fredrik Sjoholm, “Applications”, in: Iris Alvarez-Armas, Suzanne Degelaix-Moreuil (Eds), “Duplex Stainless Steels”, John Wiley & Sons Inc., 2009, pp 403-423. |
| [05] | J. K. Sahu, U. Krupp, R. N. Ghosh, H. J. Christ, “Effect of 475°C embrittlement on the mechanical properties of duplex stainless steel”, Mat. Sci. Eng. A., 508 (2009), pp 1-14. |
| [06] | F. Elsabbagh, R. Hamouda, M. Taha, “On Microstructure and Microhardness of Isothermally Aged UNS 32760 and the Effect on Toughness and Corrosion Behaviour”, J. Mat. Eng. Per., 23 (1) (2013), pp 275-284. |
| [07] | Hun Jang, Sunghoon Hong, Changheui Jang, Jae Gon Lee, “The effects of reversion heattreatment on the recovery of thermal aging embrittlement of CF8M cast stainless steels”, Mater. Des., 56 (2014), pp 517-521. |
| [08] | V. Shamanth, K. S. Ravishankar, “Dissolution of alpha-prime precipitates in thermally embrittled S2205-duplex steels during reversion-heat treatment”, Results in Physics, 5 (2015), pp 297–303 |
| [09] | Shamanth, V., Kumar, P., & Ravishankar, K. S. (2017). Effect of Heat Treatment on the High Cycle Fatigue Behaviour of S2205 Duplex Stainless Steels. Materials Today: Proceedings, 4 (10), 10798-10802. |
| [10] | Li, S. L., Zhang, H. L., Wang, Y. L., Li, S. X., Zheng, K., Xue, F., and Wang, X. T. (2013). Annealing induced recovery of long-term thermal aging embrittlement in a duplex stainless steel. Materials Science and Engineering: A, 564, 85-91. |
| [11] | Hwang, T. H., Kim, J. H., Kim, K. H., Moon, W. J., and Kang, C. Y. (2014). Effect of R-phase on impact toughness of 25Cr-7Ni-4Mo super duplex stainless steel. Metals and materials international, 20 (1), 13-17. |
| [12] | Jang, H., Hong, S., Jang, C., and Lee, J. G. (2014). The effects of reversion heat treatment on the recovery of thermal aging embrittlement of CF8M cast stainless steels. Materials and Design, 56, 517-521. |
