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Manuscript submitted December 10, 2017.
Electron beam welding of Ni-20Cr-9Mo-4Nb alloy sheets was carried out, and high-temperature tensile behaviors of base metal and weldments were studied. Tensile properties were evaluated at ambient temperature, at elevated temperatures of 625 °C to 1025 °C, and at strain rates of 0.1 to 0.001 s−1. Microstructure of the weld consisted of columnar dendritic structure and revealed epitaxial mode of solidification. Weld efficiency of ~ 90 pct in terms of strength (UTS) was observed at ambient temperature and up to an elevated temperature of 850 °C. Reduction in strength continued with further increase of test temperature (up to 1025 °C); however, a significant improvement in pct elongation is found up to 775 °C, which was sustained even at higher test temperatures. The tensile behaviors of base metal and weldments were similar at the elevated temperatures at the respective strain rates. Strain hardening exponent ‘n’ of the base metal and weldment was ~ 0.519. Activation energy ‘Q’ of base metal and EB weldments were 420 to 535 kJ mol−1 determined through isothermal tensile tests and 625 to 662 kJ mol−1 through jump-temperature tensile tests. Strain rate sensitivity ‘m’ was low (< 0.119) for the base metal and (< 0.164) for the weldment. The δ phase was revealed in specimens annealed at 700 °C, whereas, twins and fully recrystallized grains were observed in specimens annealed at 1025 °C. Low-angle misorientation and strain localization in the welds and the HAZ during tensile testing at higher temperature and strain rates indicates subgrain formation and recrystallization. Higher elongation in the weldment (at Test temperature > 775 °C) is attributed to the presence of recrystallized grains. Up to 700 °C, the deformation is through slip, where strain hardening is predominant and effect of strain rate is minimal. Between 775 °C to 850 °C, strain hardening is counterbalanced by flow softening, where cavitation limits the deformation (predominantly at lower strain rate). Above 925 °C, flow softening is predominant resulting in a significant reduction in strength. Presence of precipitates/accumulated strain at high strain rate results in high strength, but when the precipitates were coarsened at lower strain rates or precipitates were dissolved at a higher temperature, the result was a reduction in strength. Further, the accumulated strain assisted in recrystallization, which also resulted in a reduction in strength.
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H.L. Eiselstein and D.J. Tiliack: in Superalloys 718, 625 and various derivatives, E.A. Loria, ed., Minerals Metals and Materials Society, Warrendale, PA, 1991, pp. 1–14.
V. Shankar, K. Bhanu Shankar Rao and S.L. Mannan: J. Nucl. Mater. 2001, vol. 288, pp. 222–232. CrossRef
M. Jouiad, E. Marin, R.S. Devarapalli, J. Cormier, F. Ravaux, C. Le Gall and J. M. Franchet: Mater. Des. 2016, vol. 102, pp.284-296. CrossRef
A. J. Detor, R. Didomizio, R.S. Moshtaghin, N. Zhou, R. Shi, Y. Wang, D. P. Mcallister and M. J. Mills: Metal. Mater. Trans. A. 2017, https://doi.org/10.1007/s11661-017-4356-7.
R. Cozar and A. Pineau: Metal. Trans. 1973, vol. 4, pp. 47-59. CrossRef
M.D. Mathew, P. Parameswaran, and K. Bhanu Sankara Rao: Mater. Char. 2008, vol. 59, pp. 508 – 513. CrossRef
Q. Guo, D. Li, S. Guo, H. Peng and J. Hu: J. Nucl. Mater. 2011, vol. 414, pp. 440–450. CrossRef
D. Li, Q. Guo, S. Guo, H. Peng and Z. Wu: Mater. Des. 2011, vol. 32, pp. 696–705. CrossRef
X. M Chen, Y.C. Lin, D-X Wen, J-L Zhang and M. He: Mater. Des. 2014, vol. 57, pp. 568-577. CrossRef
Y. Mei, Y. Liu, C. Liu, C. Li, L. Yu, Q. Guo and H. Li : Mater. Des. 2016, vol. 89, pp. 964–977. CrossRef
K.D. Ramkumar, R. Sridhar, S. Periwal, S. Oza, V. Saxena, P. Hidad and N. Arivazhagan: Mater. Des. 1995, vol. 68, pp. 158–166. CrossRef
M. Shakil, M. Ahmad, N.H. Tariq, B.A. Hasan, J.I. Akhter, E. Ahmed, M. Mehmood, M.A. Choudhry and M. Iqbal: Vac. 2014, vol. 110, pp. 121 – 126. CrossRef
K.H. Song and K. Nakata: Mater. Trans. 2009, vol. 50A, pp. 2498–2501. CrossRef
K.H. Song and K. Nakata: Mater. Des. 2010, vol. 31, pp. 2942–2947. CrossRef
X. Xing, X. Di and B. Wang: J. Alloys Compds. 2014, vol. 593, pp. 110–116. CrossRef
L.M. Suave, J. Cormier, P. Villechaise, A. Soula, Z. Hervier, D. Bertheau, and J. Laigo: Metal. Mater. Trans. A. 2014, vol. 45, pp. 2963–2982. CrossRef
F. Cortial, J.M. Corrieu and C. Vernot-Loier: Metal. Mater. Trans. A. 1995, vol. 26(5), pp. 1273-1286. CrossRef
P.K. Korrapati, V.K. Avasarala, M. Bhushan, K.D. Ramkumar, N. Arivazhagan and S. Narayanan: Proc. Eng. 2014, vol. 75, pp. 9-13. CrossRef
A. Sukumaran, R. K. Gupta, and V. Anil-Kumar: J. Mater. Eng. Perform. 2017. https://doi.org/10.1007/s11665-017-2774-8.
J. Mittra, S. Banerjee, R. Tewari and G.K. Dey: Mater. Sci. Eng. A. 2013, vol. 574, pp. 86-93. CrossRef
AMS 2681B: Welding Electron-beam, SAE International, Warrendale, 2014, https://doi.org/10.4271/AMS2681.
ASTM E8/E8M: Standard Test Methods for Tension Testing of Metallic Materials. ASTM International, West Conshohocken, 2016, https://doi.org/10.1520/E0008_E0008M-16A.
ASTM E21: Standard Test Methods for Elevated Temperature Tension Tests of Metallic Materials, ASTM International, West Conshohocken, PA, 2017, https://doi.org/10.1520/e0021-17.
V. Anil-Kumar, R.K. Gupta, S.V.S. Narayana-Murty and A. D. Prasad: J. Alloys Compds. 2016, vol. 676, pp. 527-541. CrossRef
A. Smolej, B. Skaza and M. Fazarinc: Mater. Geoenviron. 2009, vol. 56(4), pp. 389–399.
J.S. Kim and H.W. Lee: Metal. Mater. Trans. A. 2016, vol. 47, pp. 6109-6120. CrossRef
M. Gopalakrishna-Pillai, R.K. Gupta, B. Pant and P.S. Sreejith: Trans. IIM. 2015, vol. 68(3), pp. 423-431.
P. Maj, J. Zdunek, J. Mizera, K. J. Kurzydlowski, B. Sakowicz and M. Kaminski; Met. Mater. Int. 2017, vol. 23(1), pp. 54-67. CrossRef
E.A. Lass, M.R. Stoudt, M.E. Williams, M.B. Katz, L.E. Levine, T.Q. Phan, T. H. G. Herold, and S.N.G.Daniel: Metal. Mater. Trans. A. 2017, vol. 48, pp. 5547-5558. CrossRef
J.B. Singh, A. Verma, D.M. Jaiswal, N. Kumar, R.D. Patel and J.K. Chakravartty: Mater. Sci. Eng. A. 2015, vol. 644, pp. 254–267. CrossRef
M. Sundararaman, L. Kumar, G. Eswara Prasad, P. Mukhopadhyay and S. Banerjee: Metall. Trans. A. Phys. Metall. Mater. Sci. 1999, vol.30, pp. 41–51. CrossRef
F.J. Humphreys and M. Hatherly (2004) Recrystallization and Related Annealing Phenomena, 2nd edn. Elsevier, Amsterdam.
Y.C. Lin, K.K. Li, H.B. Li, J. Chen, X.M. Chen and D.X. Wen: Mater. Des. 2015, vol. 74, pp. 108–118. CrossRef
I.J. Moore, J.I. Taylor, M.W. Tracy, M.G. Burke and E.J. Palmiere: Mater. Sci. Eng. A. 2017, vol. 682, pp. 402-409. CrossRef
M. Sundararaman and P. Mukhopadhyay: Mater. Sci. For. 1985, vol. 3, pp. 273-280.
D. Liu, X. Zhang, X. Qin and Y. Ding, Mater. Sci. Tech. 2017, https://doi.org/10.1080/02670836.2017.1300365.
A. Seret, C. Moussa, M. Bernacki, J. Cormier, and N. Bozzolo: https://hal-mines-paristech.archives-ouvertes.fr/hal-01624670, 2017.
L.M. Suave, J. Cormier, D. Bertheau, P. Villechaise, A. Soula, Z. Hervier and J. Laigo, Mater. Sci. Eng. A. 2016, vol. 650, pp. 161-170. CrossRef
- High-Temperature Tensile Behaviors of Base Metal and Electron Beam-Welded Joints of Ni-20Cr-9Mo-4Nb Superalloy
R. K. Gupta
V. Anil Kumar
- Springer US
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