Abstract
Electron Beam Welding (EBW) was performed on the highly corrosion resistance superalloy 686. The present research work investigates the metallurgical and mechanical properties of the weld joint fabricated by Electron Beam Welding technique, and the results are compared with the base metal. Optical and Scanning Electron Microscope (SEM) analysis were carried out to study the structural properties of the weld joint. The fine equiaxed dendritic structure was revealed in the Center Fusion Zone (CFZ). The columnar dendrite was noticed in the Transition Fusion Zone (TFZ). Energy-dispersive X-ray spectroscopy (EDS) analysis results show that segregation of Mo and W were noticed in the sub-grain boundary. X-ray diffraction analysis (XRD) confirmed the presence of Mo and W rich phases in the weldment. Tensile testing was carried out to evaluate the strength and ductility of the weld joint. The result revealed that the weld strength was equal to the base metal strength. The presence of Mo and W-rich intermetallic phase reduced the ductility and toughness of the weld joint compared to base metal. Bend test confirmed the defect-free weld joint that was achieved in the Electron Beam Welding technique. The corrosion rate of base metal and EBW weldment are calculated in the synthetic seawater environment with the help of Potentiodynamic polarization experiment, and corrosion rate is measured with Tafel’s interpolation technique. The corrosion test result shows that the resistance of EBW weldment is lesser than base metal corrosion resistance because of the microsegregation of alloying elements in the interdendritic region.
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References
John Dupoint N, John Lippold C and Samuel Kiser D 1999 Welding metallurgy and weldability of nickel-base alloys. New Jersey: Wiley: 49–51
Inconel alloy 686 The corrosion-resistant alloy for the 21st century. Special Metals. http://216.71.103.52/documents/Inconel%20alloy%20686,%20a%20new%20alloy.pdf. [Accessed 30 June 2015]
Special Metals. http://www.specialmetals.com/assets/documents/alloys/inconel/inconel-alloy-686.pdf. [Accessed 30 June 2015]
Perricone M J and Dupont J N 2006 Effect of composition on the solidification behavior of several Ni-Cr-Mo and Fe-Ni-Cr-Mo alloys. Metall. Mater. Trans. A. 37A: 1267–1280
Arulmurugan B and Manikandan M 2017 Development of welding technology for improving the metallurgical and mechanical properties of 21st century nickel based superalloy 686. Mater. Sci. Eng. A. A691: 126–140
Manikandan M, Arivazhagan N, Nageswara Rao M and Reddy G M 2014 Microstructure and mechanical properties of alloy C-276 weldments fabricated by continuous and pulsed current gas tungsten arc welding techniques. J. Manuf. Processes, 16: 563–572
Rowe M D, Crook P and Hoback G L 2003 Weldability of a corrosion-resistant Ni-Cr-Mo-Cu alloy. Weld J. 82: 313–320
Cieslak M J, Headley T J and Romig A D 1986 The welding metallurgy of Hastelloy alloy C-4, C-22 and C-276. Metall. Trans. A. 17A: 2035–2047
Manikandan M, Hari P R, Vishnu G, Arivarasu M, Devendranath Ramkumar K, Arivazhagan N, Nageswara Rao M and Reddy G M 1986 Investigation of microstructure and mechanical properties of super alloy C-276 by continuous Nd: YAG laser welding. Procedia Mater. Sci. 17A: 2233–2241
Guangyi M A, Dongjiang W U and Dongming G U O 2011 Segregation characteristics of pulsed laser butt welding of Hastelloy C-276. Metall. Mater. Trans. A 42A: 3853–3857
Hashim M, Sarath Raghavendra Babu K E, Muthukannan Duraiselvam and Harshad Natu 2013 Improvement of wear resistance of Hastelloy C-276 through laser surface melting. Mater. Des. 46: 546–551
Ahmad M, Akhter J I, Akhtar M, Iqbal M, Ahmed E and Choudhry M 2005 Microstructure and hardness studies of the electron beam welded zone of Hastelloy C-276. J. Alloys Compd. 390: 88–93
Radhakrishna C H, Prasad Rao K and Srinivas S 1995 Laves phase in superalloy 718 weld metals. J. Mater. Sci. Lett. 14: 1810–1812
Aman Kaur, Colin Ribton W and Balachandaran 2015 Electron beam characterization methods and devices for welding equipment. J. Mater. Process. Technol. 221: 225–232
Dongjiang M A, Dongjiang W U, Fangyong Niu and Helin Zou 2015 Microstructure evolution and mechanical property of pulsed laser welded Ni-based superalloy. Opt. Lasers Eng. 72: 39–46
Manikandan M, Arivazhagan N, Nageswara Rao M and Reddy G M 2015 Improvement of microstructure and mechanical behavior of gas tungsten arc weldments of alloy C-276 by current pulsing. Acta Metall. Sinica 28: 208–215
Balasubramanian M, Jayabalan V and Balasubramanian V 2008 Effect of pulsed gas tungsten arc welding on corrosion behavior of Ti–6Al–4 V titanium alloy. J. Mater. Des. 29: 1359–1363
Crum J R J, Shoemaker L E and Kiser S D Special alloys and overmatching welding products solve FGD corrosion problems. Special metals welding products, Technical paper. U.K. http://216.71.103.52/documents/Special%20Alloys%20and%20Overmatched%20Welding%20Products%20Solve%20FGD%20Corrosion%20Problems.pdf. [Accessed 22 June 2016]
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ARULMURUGAN, B., AGILAN, M., JEROME, S. et al. Investigation of metallurgical and mechanical properties of 21st century nickel-based superalloy 686 by electron beam welding technique. Sādhanā 43, 117 (2018). https://doi.org/10.1007/s12046-018-0850-x
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DOI: https://doi.org/10.1007/s12046-018-0850-x